UPDATE 2-Syrian Kurdish fighters say withdrew in line with ceasefire - U.S. officials

(Updates with second official, Schumer, background)

By Humeyra Pamuk

WASHINGTON, Oct 22 (Reuters) - The commander of Kurdish-led SDF fighters has informed the United States that it has carried out all of its obligations under a U.S.-brokered truce to withdraw forces from a border area with Turkey in northeastern Syria, a senior administration official said on Tuesday.

"A letter came in from General Mazloum...that he had carried out all of his obligations under the arrangement that we had done with the Turks...to withdraw all YPG forces out of the Turkish-controlled safe zone," the senior administration official told reporters, referring to Mazloum Abdi, the head of Washington's former allies in the fight against Islamic State.

A second administration official cited intelligence showing that SDF had left the area.

The first official said Ankara and Washington have been in close contact to verify that the withdrawal has taken place to ensure Turkey's pause in its military offensive into Syria would turn into a permanent halt as agreed in Turkey last week.

The five-day truce to allow the withdrawal of Kurdish YPG fighters from the border area ends at 10 p.m. (1900 GMT) on Tuesday. President Tayyip Erdogan has said Turkey could then press on with fighting.

"We think that Turkey in the end will agree that the withdrawal has taken place under the terms of the agreement. This means that the Turkish pause becomes a Turkish halt in military operations," the first official said.

He said if Ankara fails to cease operations, U.S. sanctions will follow.

"Any Turkish kinetic military operation that moves forward at the end of this 120 hours, when they’re supposed to move into an even more...rigid and formal ceasefire under the name halt....will lead to us concluding that Turks have violated our agreement with inevitable sanctions."

The second official noted that sanctions imposed on Turkey last week were not yet lifted.

"We will not lift the sanctions until there is a ceasefire," the official said. He added that the United States was maintaining a presence for fighting ISIS and protecting oil fields.

Trump said on Monday he did not want to leave any American troops in Syria, aside from a small number to secure oil production.

Washington was keeping a close eye on Erdogan's visit to Sochi for talks with Russian President Vladimir Putin, the first official said.

Turkey and Russia agreed on Tuesday that once the YPG militia are removed to beyond 30 km (19 miles) from the Turkish border, their troops will jointly patrol a narrower strip of land in a "safe zone" Ankara has long sought in northern Syria.

Senate Democratic leader Chuck Schumer slammed the Trump administration's refusal to brief U.S. senators on Syria policy and said Democrats were set to meet with Brett McGurk, the former president envoy against ISIS, at a special caucus meeting scheduled for Wednesday.

"The American people should be very concerned that the Trump administration does not seem to have any plan to secure the enduring defeat of ISIS in Syria," Schumer said. (Additional reporting by Steve Holland and Patricia Zengerle Reporting by Humeyra Pamuk; Editing by Lisa Shumaker and Sonya Hepinstall)