(Updates with more quotes from Esper, background)
By Idrees Ali
ABOARD A U.S. MILITARY AIRCRAFT, Oct 19 (Reuters) - U.S. Defense Secretary Mark Esper said on Saturday that all of the nearly 1,000 troops withdrawing from northern Syria are expected to move to western Iraq to continue the campaign against Islamic State militants and "to help defend Iraq."
On Thursday, Turkey agreed in talks with U.S. Vice President Mike Pence to a five-day pause in an offensive into northeastern Syria to allow time for the Kurdish fighters to withdraw from a "safe zone" Ankara aims to establish near the Turkish border with Syria.
The truce also aimed to ease a crisis triggered by President Donald Trump's abrupt decision earlier this month to withdraw all 1,000 U.S. troops from northern Syria, a move criticized in Washington and elsewhere as a betrayal of loyal Kurdish allies who had fought for years alongside U.S. troops against Islamic State.
"The U.S. withdrawal continues apace from northeastern Syria... we're talking weeks not days," Esper told reporters en route to the Middle East, adding that it was being carried out through aircraft and ground convoys.
"The current game plan is for those forces to re-position into western Iraq," Esper said, adding that they would number about one thousand.
He said the mission for those troops would be to "help defend Iraq" and carry out a counter-Islamic State mission. A senior U.S. defense official clarified that the situation was still fluid and plans could change.
Any decision to send additional U.S. troops to Iraq is likely to be heavily scrutinized in a country where Iran has been steadily amassing influence.
"That is the current game plan, things can change between now and whenever we complete the withdrawal but that is the game plan right now," the senior official added.
It is unclear whether the U.S. troops will use Iraq as a base to launch ground raids into Syria and carry out airstrikes against Islamic State militants.
The additional U.S. troops would add to the more than 5,000 American troops already based in the country, training Iraqi forces and helping to ensure that Islamic State militants do not resurge.
While Esper said he had spoken with his Iraqi counterpart and will continue to have conversations in the future, the move will likely be viewed with skepticism by some in Iraq.
Iraq is in the midst of a political crisis, as mass protests have led to more than 100 deaths and 6,000 injuries during the week starting Oct. 1.