WASHINGTON: Newly appointed Pentagon chief Christopher Miller signalled Saturday that he could accelerate the withdrawal of US troops from Afghanistan and the Middle East, saying, "It's time to come home."

"All wars must end," Miller, named acting defence secretary by President Donald Trump on Monday, said in his first message to the US armed services.

He said that the US is committed to defeating Al Qaeda, 19 years after the September 11 attacks on the United States, and is "on the verge of defeating" the group.

"Many are weary of war - I'm one of them," he wrote in the message, dated Friday but posted early Saturday on the Defence Department's website.

"But this is the critical phase in which we transition our efforts from a leadership to supporting role," he said.

"Ending wars requires compromise and partnership. We met the challenge; we gave it our all. Now, it's time to come home."

Miller did not mention specific US troop deployments, but the reference to Al Qaeda appeared to single out Afghanistan and Iraq, where US troops were deployed after the September 11 attacks.

The former US special forces officer and counterterrorism expert was named to lead the Department of Defence after Trump fired Mark Esper.

Esper cut US forces in Afghanistan by nearly two-thirds in the wake of the February 29 US-Taliban peace deal.

But, drawing a line, he said he would hold troop numbers at 4,500 after this month until the Taliban, as they negotiate with the government in Kabul, follow through on pledged reductions in violence.

Trump, however, has pushed for continued cuts, tweeting that he wants the troops "home by Christmas," December 25.-AFP