US Senate(WASHINGTON) — Sen. John McCain, R-Ariz. criticized military strategy in Afghanistan Monday, less than two weeks after three U.S. soldiers were killed in an attack for which the Taliban later claimed responsibility.

McCain cited the deaths, in which an Afghan soldier turned his gun on the Americans, as rationale to “turn the situation around in Afghanistan,” in a statement Monday.

“After nearly 16 years of war, we are at a stalemate in Afghanistan,” said McCain in the release. “Worse, we have no strategy to end that stalemate and achieve victory.”

The senator, who chairs the Senate Armed Services Committee, pointed to testimony given by Defense Secretary James Mattis last week, who said that the U.S. is not winning in Afghanistan.

There are currently 8,400 U.S. soldiers in Afghanistan involved in training and advising the Afghan military, 2,000 of which are involved in counterterrorism operations against al-Qaeda and the ISIS affiliate in Afghanistan.

Last week, President Donald Trump authorized Mattis to increase the military presence in Afghanistan. U.S. military commanders have recommended 2,000 to 5,000 additional soldiers in the country, according to U.S. officials. Mattis has not yet made a determination on troop levels.

“We cannot keep going like this,” said McCain. “If the administration fails to develop a strategy for success, Congress will need to play a greater role.”

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