Afghan Taliban militants now control about half of the war-torn country's 419 district centers, a top U.S. general said on Wednesday.

"Strategic momentum appears to be sort of with the Taliban," General Mark Milley, chairman of the U.S. Joint Chiefs of Staff, told a press conference.

"There's a possibility of a complete Taliban takeover, or the possibility of any number of other scenarios," Milley said. "I don't think the end game is yet written."

While the militants have yet to capture any of the country's 34 provincial capitals, they are pressuring about half of them, he said.

Afghan security forces are consolidating their positions to protect those major urban centers including Kabul, he added.

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Afghan govt, Taliban to meet again after lack of progress

The Afghan provinces have seen heavy battles between the Taliban and government security forces since the start of the withdrawal of the U.S.-led forces from Afghanistan in early May.

U.S. President Joe Biden has set a formal end to the U.S. military mission in Afghanistan for August 31, days ahead of his original September 11 deadline.

U.S. Central Command said last week over 95 percent of the withdrawal had been completed.

More than 2,400 U.S. troops have been killed in Afghanistan over the past two decades, with 20,000 wounded, according to the Pentagon.

Estimates show that over 66,000 Afghan troops have been killed, and over 2.7 million people have had to leave their homes.