U.S. Army General John Nicholson | Alex Wong/Getty Images US commander tells Congress: More troops needed in Afghanistan General John Nicholson said more forces were needed to sufficiently ‘train, advise and assist’ the Afghans.

WASHINGTON — The top U.S. commander in Afghanistan told Congress Thursday a few thousand more troops are needed there to break the stalemate between Afghan forces and the Taliban.

Army Gen. John Nicholson told the Senate Armed Services Committee he had enough U.S. and NATO troops for counterterrorism operations in Afghanistan, but that more were needed to sufficiently “train, advise and assist” the Afghan forces.

“We have a shortfall of a few thousand,” Nicholson said. “This is in the NATO train-advise-and-assist mission, so this can come from U.S. and its allies.”

Currently, there are 8,400 U.S. troops in Afghanistan and another 5,000 troops come from NATO countries.

Again on Thursday, Senate Armed Services Chairman John McCain slammed the Obama administration for installing the U.S. troop limits, charging the drawdown of U.S. forces was more about “American politics than the conditions on the ground.”

The Arizona Republican criticized the Obama administration over the troop caps as well as previous restrictions on U.S. rules of engagement against the Taliban, saying the Obama plan was always “doomed to failure.”

He urged the Trump administration to boost U.S. forces in Afghanistan.

“This new administration has the opportunity to turn the page and finally give the commanders the resources and authorities they need to seize the initiative and force enemy to react, instead of the other way around,” McCain said.

Senator Jack Reed of Rhode Island, the top Democrat on the Armed Services panel, endorsed more “flexibility” on the number of U.S. military personnel in Afghanistan.

President Donald Trump has not detailed his plans for the war in Afghanistan, but Nicholson’s comments suggest the Pentagon is likely to seek a larger U.S. presence from the White House.

Nicholson, who described the current situation in Afghanistan as a stalemate, said he’s in discussions with U.S. Central Command chief Gen. Joseph Votel and Joint Chiefs Chairman Gen. Joe Dunford about adding troops for the training mission. He expects Defense Secretary Jim Mattis to discuss the issue with allies next week at a NATO ministerial meeting.

The additional troops would help NATO forces “thicken our advisory effort,” Nicholson said.

U.S. troops are conducting both counterterrorism operations as well as the advisory role, with the goal of training Afghan forces to be able to fight the Taliban on their own.

Afghan forces have taken thousands of casualties in the past two years after taking the lead in security operations, and the Taliban has gained territory from the Afghan government over the past year.

Nicholson also raised the issue of over-reliance on contractors in Afghanistan. The U.S. military currently has a two-to-one contractor-to-troop ratio, he said.

“What we’ve done in some cases is substitute contractors for soldiers in order to meet force manning levels,” Nicholson said.

He argued that deploying only partial units — keeping maintenance workers at home, for instance, to use contractors in Afghanistan — ultimately winds up costing the U.S. government more money.