Donald Trump's leaking of classified intelligence to Russians 'far worse than reported'

Mr Trump may have jeopardised cooperation from an ally familiar with inner workings of Isis

It is unlikely Mr Trump has broken any law, as president he has the broad authority to declassify government secrets - but US allies and intelligence officials may be more wary about sharing future top secret details with the President (Reuters)

Donald Trump disclosed highly classified information to Russia's foreign minister about a planned Isis operation, US officials have said.

Citing current and former US officials, the Washington Post said Mr Trump shared details about an Isis terror threat related to the use of laptop computers on aircraft with Russian foreign minister Sergey Lavrov and Russian ambassador to the US Sergey Kislyak.

The anonymous officials told the Washington Post the information the President relayed during the Oval Office meeting had been provided by a US partner through an intelligence-sharing arrangement. They said it was considered so sensitive that details have been withheld from allies and tightly restricted even within the US government.

A separate official told Buzzfeed news that the extent of classified intelligence information disclosed was "far worse than what has already been reported".

The White House denounced the allegations as incorrect.

"The story that came out tonight as reported is false," H R McMaster, Mr Trump's national security adviser, told reporters at the White House, adding that the leaders reviewed a range of common threats including to civil aviation.

"At no time were intelligence sources or methods discussed. The president did not disclose any military operations that were not already publicly known... I was in the room. It didn't happen," he said.

The White House also released a statement from Secretary of State Rex Tillerson, who said the Oval Office meeting focused on counterterrorism, and from Deputy National Security Adviser Dina Powell, who called the Washington Post story false.

The Washington Post story - which was later confirmed by The New York Times and BuzzFeed News - does not claim that Mr Trump revealed any specific information about how the intelligence was gathered.

Still, it will only heighten Mr Trump's strained relations with intelligence workers and former officials, who view Russia as an adversary.

If true, the breach was ill-timed, coming a day after Mr Trump fired former FBI director James Comey, who was leading an investigation into Russian meddling in the presidential election.

Mr Trump's first national security adviser, Michael Flynn, was fired after he misled vice president Mike Pence about conversations he had with Mr Kisylak.

It is unlikely Mr Trump has broken any law. As president, he has the broad authority to declassify government secrets.

The Washington Post said the intelligence partner had not given the United States permission to share the material with Russian officials.

By doing so, Mr Trump would have jeopardised cooperation from an ally familiar with the inner workings of Isis, and make other allies - or even US intelligence officials - wary about sharing future top secret details with the President.

Additional reporting by agencies