US Republican Senate chief rebukes Trump with Syria amendment

The Republican leader of the US Senate, Mitch McConnell, delivered a rare rebuke to Donald Trump in legislation that questions the president's decision to pull US troops out of Syria.

The amendment to a broader Middle East Policy bill easily passed a preliminary procedural vote on Thursday 68 to 23, with substantial support from both Democrats and Republicans.

McConnell, who rarely criticises Trump openly, said earlier this week that the amendment "would acknowledge the plain fact that al-Qaeda, ISIS, and their affiliates in Syria and Afghanistan continue to pose a serious threat to our nation".

"It would recognise the danger of a precipitous withdrawal from either conflict and highlight the need for diplomatic engagement and political solutions to the underlying conflicts in Syria and Afghanistan," he said.

The procedural vote to cut off debate on the amendment would be added to a broader Middle East security bill that is likely to come up for a final Senate vote next week.

The amendment has no real impact on policy but signifies the broad opposition even in Trump's own party to a rapid removal of US troops from Syria, which the president announced in December.

Still, the bill also includes an anti-boycott, divestment and sanctions (BDS) amendment that may prove difficult to pass in the Democratic-controlled House of Representatives.

If the bill passes the Senate, it would then go to the House for a vote. If the House passes the legislation, it would head to the White House, but Trump has already vowed to veto the bill.

In the case of a veto, the bill would return to the Senate where a two-thirds majority vote could override the veto.

Ahead of the preliminary vote, Republicans Senator Marco Rubio said Trump's planned withdrawal was a "bad idea".

"That announcement alone has undermined our credibility in the eyes of our allies," he added.

Trump has come under mounting pressure from both parties and the bureaucracy over a number of his foreign policy measures.

On Tuesday, the top US intelligence chief said the Islamic State (IS) group still has "thousands" of fighters that it could rebuild into a cohesive force in any vacuum left in the war-torn country.

The next day, Trump took issue with that challenge to his stance, calling his intelligence chiefs "extremely passive and naive," adding: "Perhaps Intelligence should go back to school!"