Top Senate Republican warns 'precipitous' Syria pullout benefits Russia, Iran

The top Republican in Congress warned Monday that an abrupt pullback of US troops from Turkey's border with Syria would only benefit Russia, Iran and President Bashar al-Assad's government in Damascus.

Senate Majority Leader Mitch McConnell became the most senior lawmaker in Donald Trump's party to oppose the president's announced decision to withdraw from certain positions in northern Syria, one that effectively abandons the Kurds, one of Washington's main allies in the war against Islamic State group militants.

"A precipitous withdrawal of US forces from Syria would only benefit Russia, Iran, and the Assad regime," McConnell said in a statement, joining a broad bipartisan outcry on Capitol Hill.

"And it would increase the risk that ISIS and other terrorist groups regroup," he said, using an acronym for the Islamic State group.

McConnell is a vital Trump ally in Congress and has the power to decide which bills get brought to the Senate floor for a vote.

In a veiled warning to the White House, he recalled how a veto-proof bipartisan "supermajority" in the Senate voted on a measure last January that criticized Trump's order to withdraw all 2,000 American troops from Syria.

Trump's full withdrawal did not proceed, but it shocked allies and led to the resignation of Pentagon chief Jim Mattis.

"The conditions that produced that bipartisan vote still exist today," McConnell said, noting the Islamic State group and Al-Qaeda "remain dangerous forces in Syria" and that the country's ongoing civil war poses significant security risks.

"I urge the president to exercise American leadership to keep together our multinational coalition to defeat ISIS and prevent significant conflict" between Turkey and US counter-terrorism partners in Syria.

A furious Senator Lindsey Graham, another Trump ally, said earlier Monday that he would introduce a resolution "opposing and asking for reversal of this decision" to pull back from parts of northern Syria if Trump goes ahead.

Graham then added that he and Senate Democrat Chris Van Hollen would introduce a sanctions measure against Turkey if its forces invade Syria "and will call for their suspension from NATO if they attack Kurdish forces."