At least 14 Trump associates spoke to Russians during campaign and transition now subject to Mueller investigation

Level of contact is 'extremely unusual', according to former Obama and McCain campaign officials

The Russian ambassador. A deputy prime minister. A pop star, a weightlifter, a lawyer, a Soviet army veteran with alleged intelligence ties.

Again and again and again, over the course of Donald Trump's 18-month campaign for the presidency, Russian citizens made contact with his closest family and friends, as well as figures on the periphery of his orbit.

Some offered to help his campaign and his real estate business. Some offered dirt on his Democratic opponent. Repeatedly, Russian nationals suggested Mr Trump should hold a peace-making sit-down with Vladimir Putin - and offered to broker such a summit.

In all, Russians interacted with at least 14 Trump associates during the campaign and presidential transition, public records and interviews show.

"It is extremely unusual," said Michael McFaul, who served as ambassador to Russia under President Barack Obama. "Both the number of contacts and the nature of the contacts are extraordinary."

As special counsel Robert Mueller III slowly unveils the evidence he has gathered since his appointment in May 2017, he has not yet shown that any of the dozens of interactions between people in Mr Trump's orbit and Russians resulted in any specific coordination between his presidential campaign and Russia.

But the mounting number of communications that have been revealed occurred against the backdrop of "sustained efforts by the Russian government to interfere with the US presidential election," as Mr Mueller's prosecutors wrote in a court filing last week.

The special counsel's filings have also revealed moments when Russia appeared to be taking cues from Mr Trump. In July 2016, the then-GOP candidate said at a news conference, "Russia, if you're listening, I hope you're able to find the 30,000 emails that are missing," referring to messages Democratic candidate Hillary Clinton had deleted from a private account. That day, the Russians made their first effort to break into servers used by Ms Clinton's personal office, according to court documents.

As Americans began to grip the reality that a hostile foreign power took active steps to shape the outcome of the race, Mr Trump and his advisers asserted they had no contact with Russia.

Two days after Mr Trump was elected president, a top Kremlin official caused a stir by asserting Mr Trump's associates were in contact with the Russian government before the election.

"I don't say that all of them, but a whole array of them supported contacts with Russian representatives," Deputy Foreign Minister Sergei Ryabkov told the Interfax news agency on 10 November 2016.

The claim was met with a hail of denials. Hope Hicks, then Mr Trump's top spokesperson, responded, "It never happened. There was no communication between the campaign and any foreign entity during the campaign."

After Mr Trump took office, in February 2017, he reiterated the denial. "No. Nobody that I know of," the president told reporters when asked whether anyone who advised his campaign had contact with Russia. "I have nothing to do with Russia. To the best of my knowledge, no person that I deal with does."

It is now clear that was not true.

Mr Trump's oldest children, Donald Trump Jr and Ivanka Trump, interacted with Russians who were offering to help the candidate.

Ivanka's husband, top campaign adviser Jared Kushner, as well as Mr Trump's campaign chairman Paul Manafort, his personal lawyer Michael Cohen and his longest-serving political adviser, Roger Stone, also had contact with Russian nationals.

Veterans of past White House bids said that so much interplay with representatives of a foreign adversary is highly unusual.

"This is different in kind than anything I have ever heard of before," said Trevor Potter, who served as general counsel to Senator John McCain's presidential campaign in 2008. McCain, he noted, travelled the globe as a member of the Senate, but his contacts with foreign government officials generally occurred in consultation with the State Department and involved questions of policy - not personal business or his own electoral concerns.

The number of known interactions has grown since last year, when The Washington Post tallied that at least nine Trump associates had contacts with Russians during the campaign or presidential transition.

At the time, then-White House lawyer Ty Cobb said, "I think the American public can fully appreciate that those are isolated, obviously disconnected events, quite small in number for a presidential campaign."

Trump attorney Jay Sekulow declined to comment on Sunday.

The president has repeatedly denied people close to him coordinated with Russia, tweeting frequently, "NO COLLUSION!"

New court documents filed by Mr Mueller's prosecutors in the past two weeks revealed the Russian outreach was more extensive than previously known.

In November 2015, Cohen spoke with a Russian national who claimed to be a "trusted person" in the Russian Federation offering the campaign "political synergy" and "synergy on a government level," according to a memo filed by the special counsel on Friday.

The Russian national repeatedly proposed a meeting between Mr Trump and Mr Putin, prosecutors wrote, saying that a sit-down between the two men could have a "phenomenal" impact because there is "no bigger warranty in any project" than Mr Putin's backing.

The details of the episode matches descriptions of an interaction Cohen had at the time with Dmitry Klokov, a well-connected Russian athlete, which was first reported by BuzzFeed News.

An Olympic weightlifter turned entrepreneur, Mr Klokov sells training equipment, clothing and fitness programmes worldwide from his base in Moscow.

Asked on Saturday via a message to his Instagram account about his reported communications with Cohen, Mr Klokov responded with three laughing-in-tears emoji and the words: "This is someone's nonsense."

Mr Klokov's wife reached out to Ivanka Trump in October 2015, saying she had connections in the Russian government and could help her father build a Trump Tower in Moscow, a project he had long sought, according to a person familiar with the interaction.

Ivanka Trump did not know the woman but forwarded her contact information to Cohen, who later connected with Mr Klokov, the people familiar with the exchanges said.

After an initial conversation, prosecutors said Cohen did not pursue a meeting through the Russian national because he believed he already had connections to the Russian government through a business partner.

That partner, Russian-born developer Felix Sater, said in an interview that he had been unaware of Cohen's contact with Mr Klokov.

Cohen, who had worked for Mr Trump for a decade and urged him to run for president years before the celebrity mogul launched his bid in 2015, was focused on his boss' relationship with Russia from the campaign's earliest days.

In September 2015, Cohen told Sean Hannity during an appearance on the Fox News host's radio programme that there was a "better than likely" chance Mr Trump and Mr Putin would meet while Mr Putin was in New York for the annual meeting of the United Nations General Assembly then under way.

"People want to meet Donald Trump. They want to know Donald Trump," Cohen told Mr Hannity.

Last week, prosecutors revealed Cohen admitted he conferred with Mr Trump about the idea "before reaching out to gauge Russia's interest in such a meeting."

Mr Mueller said Cohen has corrected past misstatements about "his outreach to the Russian government during the week of the United Nations General Assembly." Court filings provided no additional details about the outreach.

The special counsel also revealed in recent weeks that Cohen communicated with the Kremlin about efforts to build a Trump Tower in Moscow. Cohen spoke by phone with an assistant to Mr Putin's spokesperson, Dmitry Peskov, after asking Mr Peskov for government help propelling the project.

Prosecutors called the real estate development - pursued even as Mr Trump was campaigning for the Republican nomination - a "lucrative business opportunity" that could have produced hundreds of millions for Mr Trump's company, noting that it probably would have required Russian government help for completion.

Mr Mueller also indicated his team has been gathering evidence about Manafort's interactions with Konstantin Kilimnik, a Russian army veteran who worked for Manafort in the Kiev office of his political consulting company.

Mr Mueller's team accused Manafort of lying repeatedly in interviews with investigators about his interactions with Mr Kilimnik, who has been assessed by the FBI to have ties to Russian intelligence and met with Manafort twice during the campaign.

Details about those alleged falsehoods were redacted from the filing.

The Post has previously reported that Manafort asked Mr Kilimnik to extend an offer of "private briefings" about the campaign to Oleg Deripaska, a top Russian businessman who is close to Mr Putin. Mr Deripaska's spokesperson has said no such briefings took place.

Some outreach came directly from the Russian government. Russian Ambassador Sergey Kislyak met several Trump advisers, including then-Senator Jeff Sessions, R-Ala, at the Republican National Convention. Trump aide Carter Page has said he was greeted by Deputy Prime Minister Arkady Dvorkovich after delivering a speech in Moscow in July 2016.

People close to Mr Trump were twice offered damaging information about Ms Clinton, a particular foe of Mr Putin whom he blamed for fomenting protests against his regime while she was secretary of state.

In June 2016, Mr Trump's son Donald Trump Jr met with a Russian lawyer, whom he was told would provide dirt on Ms Clinton. The meeting was arranged by billionaire Moscow developer Aras Agalarov and his pop star son Emin.

The attendees of the Trump Tower gathering, which also included Manafort and Mr Kushner, said lawyer Natalia Veselnitskaya offered nothing helpful. But several attendees described to congressional investigators Trump Jr's eagerness for the Russian's assistance, according to transcripts of their testimony.

In addition, Russians repeatedly suggested a meeting between Mr Trump and Mr Putin might be a good idea.

Months after the Russian weightlifter broached the idea of such a summit with Cohen, Ivan Timofeev, a director of a Moscow think tank with ties to the Russian foreign ministry, discussed a Trump-Putin meeting with George Papadopoulos, a Trump foreign policy adviser.

A London-based professor also connected Mr Papadopoulos to a Russian woman whom the Trump adviser believed was Mr Putin's niece.

Some of the interactions between Trump associates and Russians were low-level, speculative discussions.

"The kind of people we are talking about are not the kind of people you talk to about US-Russia relations, the future of the START (Strategic Arms Reduction Treaty) treaty and so on," Mr McFaul said.

But he said the Russians would have taken note of the willingness of Trump aides to engage.

"I think the Russians would nurture those contacts and see them as a way to establish relationships that could be useful for Putin and his government," he said.

The Washington Post