US President Donald Trump greets soldiers after speaking to the troops during a surprise Thanksgiving day visit at Bagram Air Field, on November 28, 2019 in Afghanistan.
Washington CNN  — 

Senior US military commanders have been discussing options for significantly reducing the US troop presence in Afghanistan earlier than planned, according to several defense officials.

The closely held discussions were sparked in part by worries that President Donald Trump may want to withdraw troops before voters go to the polls in order to fulfill his 2016 campaign promise to bring troops home, the officials said.

Trump has said he would like to pull American soldiers out of Afghanistan ahead of the timeline set out in a February agreement with the Taliban – a prospect that raises concerns within the Pentagon about troop safety and the possibility it could spark renewed violence in the country.

The New York Times first reported the Pentagon plans.

It is not clear if Trump has asked for a full withdrawal or would agree to let some number of troops stay, but military leaders could present Trump with options for a decision within days.

‘As soon as reasonable’

Asked Tuesday if he plans to have troops home from Afghanistan by Thanksgiving, Trump said that he hopes to have them out “as soon as reasonable.”

“We’re really not acting as soldiers,” the President said, speaking in the Rose Garden. “We’re acting as police and we’re not sent there to be policemen, but we’re there 19 years and, yeah, I think that’s enough, and they understand. We’re having very positive talks. We want to bring our soldiers back home.”

“We’re not only talking about there. We’re talking about other countries, also,” he added.

Asked if Thanksgiving Day was his target for a US exit, Trump said, “No. I have no target, but as soon as reasonable, over a period of time, but as soon as reasonable.”

One defense official points out an early withdrawal would change the US policy from a conditions-based drawdown to one with a timed deadline, potentially risking a new round of Taliban violence. US commanders are also making clear that a precipitous withdrawal could put at risk any troops that remain in Afghanistan until the end of the drawdown.

Trump criticized his predecessor President Barack Obama for announcing a timed withdrawal from Afghanistan in the past. And in a 2017 speech, Trump said “how counterproductive it is for the United States to announce in advance the dates we intend to begin or end military options,” adding that “America’s enemies must never know our plans or believe they can wait us out.”

For now, officials are banking that the President’s priority on fighting terrorism could mean he will agree to have some troops stay.

Under the agreement with the Taliban, the US would pull all its troops from Afghanistan 14 months after it was signed in February, on the condition that the Taliban committed to preventing Al Qaeda or other terrorist groups from using Afghan territory and pursued intra-Afghan negotiations for a permanent cease fire. Those talks have not yet begun.

The US had already agreed to drawdown to 8,600 troops by July or 135 days after the signing of a conditional peace agreement. CNN reported in April that the US already has fewer than 10,000 US troops in Afghanistan, putting the Trump administration ahead of schedule on its drawdown commitment in the deal. There were a total 12,000 to 13,000 US troops in the country earlier this year.

The options developed by senior US military leaders, including General Scott Miller, the overall commander in Afghanistan, sketch out a variety of scenarios and the risks attached to each of them. The options have already been discussed with Gen. Frank McKenzie, the head of the US Central Command, and top Pentagon leadership including Secretary of Defense Mark Esper and Chairman of the Joint Chiefs of Staff General Mark Milley, officials say.

The discussions are being tightly held because of concern an impulsive decision to quickly go to zero could have significant implications for Afghanistan immediate security officials say.

Officials have long sad they could still conduct counterterrorism missions, including those against ISIS, with 8,600 troops. But if all troops are ordered out, it would be difficult to conduct those missions by air from bases outside Afghanistan and a US withdrawal would almost certainly lead to the drawdown of NATO troops as well.

CNN’s Maegan Vazquez contributed to this report