Top Republicans turning on Trump over Middle East troop withdrawals: 'They’re celebrating in Moscow'

'We are setting in motion the loss of all our gains and paving the way toward a second 9/11,' Lindsey Graham says

Senior Republicans are turning against Donald Trump’s “devastating” moves to withdraw US troops from war zones in the Middle East.

Earlier this week, the US president announced a dramatic U-turn in policy when he ordered the full withdrawal of American forces from Syria. He was also reported to be considering stripping back troop numbers in Afghanistan.

The issue is widely considered to have sparked the resignation of defence secretary James Mattis, who on Thursday quit in a letter that appeared to be critical of the president’s foreign policy approach.

“Because you have the right to have a Secretary of Defence whose views are better aligned with yours ... I believe it is right for me to step down from my position,” he said, in a message that conspicuously omitted any praise of the president.

Lindsey Graham, a Republican senator and vocal supporter of Mr Trump, suggested on Twitter troop withdrawals in Afghanistan could ultimately spark a terrorist incident on US soil.

“The conditions in Afghanistan – at the present moment – make American troop withdrawals a high risk strategy,” he wrote.

“If we continue on our present course we are setting in motion the loss of all our gains and paving the way toward a second 9/11.”

Marco Rubio, a Republican senator for Florida, branded Mr Trump’s Syrian withdrawal a “colossal mistake” that would result in “grave consequences”.

“Our role in Syria is nothing like Iraq or Afghanistan,” he said on Twitter. “Isis has members who spend all day plotting and inspiring attacks against Americans. The more territory they control the easier it is for them to do that.”

In rare public criticism of Mr Trump, senate majority leader Mitch McConnell said he was “distressed” at Mr Mattis’ departure from government.

In the wake of Mr Mattis’ exit, former Republican presidential candidate John Kasich tweeted: “This chaos, both foreign and domestic, is putting America in danger and must stop immediately.”

Republican congressman Adam Kinzinger told Fox News that, despite wanting to support Mr Trump “in every way I can, the president’s decisions would be devastating for foreign policy”.

“They’re celebrating in Moscow and Tehran right now. They’re trembling in Tel Aviv. And in Washington we’re confused, because nobody saw this coming.”

Some Republicans, however, were in favour of Mr Trump's decision.

"By definition this is the opposite of an Obama decision," senator Mike Lee told Fox News. "Obama got us involved, Trump's taking us out. Congress has never declared war ... on Syria. We shouldn't be there anyway without congress doing that."

One politician very much in support of Mr Trump was his Russian counterpart, Vladimir Putin.

“With regards to the victory over Isis, on the whole I agree with the president of the United States,” Mr Putin said during an annual news conference. He added that Mr Trump’s decision on Syria was “correct”.