The U.S. decision to cut up to $2 billion in military assistance to Pakistan is not expected to affect the supply lines the U.S. relies upon for its Afghanistan operations, Defense Secretary Jim Mattis said Friday.

The State Department announced the cuts Thursday in order to pressure the Pakistani government to “take decisive action” against extremist groups that operate from Pakistan, including the Haqqani Network and the Taliban.

The announcement followed President Donald Trump accusing Pakistan of “lies and deceit” in his first Tweet of the new year. “They give safe haven to the terrorists we hunt in Afghanistan, with little help. No more!” Trump tweeted Jan. 1.

On Friday, Pakistan defended its record against fighting extremism and left open the possibility that the U.S. decision to cut aid could indeed impact U.S. operations there.

“We are engaged with the U.S. administration on the issue of security cooperation and await further details,” Pakistan’s Ministry of Foreign Affairs said in a statement. “Impact of [the] U.S. decision on pursuit of common objectives is also likely to emerge more clearly in due course of time.”

On Friday, a Trump administration official outlined the total cuts. The $2 billion includes about $1 billion in planned military assistance, including the $255 million in foreign military financing that was already on hold, and $900 million in Coalition Support Funds that would reimburse Pakistan for counterterrorism operations.

In an off-camera briefing with reporters on Friday, Mattis took a more conciliatory approach. He acknowledged Pakistan’s anti-terrorism efforts and emphasized that aid would be restored if the U.S. sees evidence of renewed effort by Pakistan.

“I think many of you are aware that Pakistan has lost more troops, total, than all the NATO coalition combined,” in the counterterrorism fight inside Pakistan, Mattis said.

“As you saw in the statement, there were very specific words that said we’re still working with Pakistan, and we would restore the aid if we see decisive movements against the terrorists who are as much of a threat against Pakistan as they are against us,” Mattis said, referring to the State Departments official announcement on the aid cuts Thursday.

Mattis said he had “no indication” from the Pakistani government that the U.S. decision would impact the ground lines of communication, or GLOCs, that supply convoys use to deliver food and equipment to U.S. bases in Afghanistan. The U.S. has alternative routes to supply its forces, including flying supplies in, but that is much more expensive.

Trump had been hinting at cutting off additional aid to Pakistan since he announced his South Asia Strategy last year. The South Asia strategy took a regional approach, including engagement with India and Pakistan, to trying to end the now 17-year war in Afghanistan.

“We have been paying Pakistan billions and billions of dollars at the same time they are housing the very terrorists that we are fighting. But that will have to change, and that will change immediately,” Trump said in a speech in Virginia in August, when he outlined the new strategy.

Mattis said that Thursday’s announcement was in line with the strategy, and would be accompanied by continued engagement with Pakistan.

“Everything we are doing is integrated into the strategy,” Mattis said. “Obviously we’ll continue talking with one another.”

The Associated Press contributed to this report.

Tara Copp is the Pentagon Bureau Chief for Military Times and author of the award-winning military nonfiction "The Warbird: Three Heroes. Two Wars. One Story."

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