WASHINGTON (AP) Acting Defense Secretary Christopher Miller said Tuesday the U.S. will reduce troop levels in Iraq and Afghanistan by mid-January, asserting that the decision fulfills President Donald Trump s pledge to bring forces home from Americas long wars even as Republicans and U.S. allies warn of the dangers of withdrawing before conditions are right.

The plan will accelerate troop withdrawals from Iraq and Afghanistan in Trumps final days in office, despite arguments from senior military officials in favor of a slower, more methodical pullout to preserve hard-fought gains. Trump has refused to concede his election loss to Democrat Joe Biden , who takes office Jan. 20, just five days after the troop withdrawals are to finish.

Miller, who refused to take questions from reporters after reading a prepared statement before TV cameras at the Pentagon, said the U.S. will reduce troop levels in Afghanistan from more than 4,500 to 2,500, and in Iraq from about 3,000 to 2,500.

Speaking a week after taking over for former Defense Secretary Mark Esper , who was fired by Trump, Miller notably did not say that the drawdown plan had been recommended or endorsed by Gen. Mark Milley, chairman of the Joint Chiefs of Staff, or by other senior military officers. He said only that military commanders had agreed to execute it.

Miller said the U.S. remains ready to respond if conditions in Afghanistan or Iraq deteriorate.

If the forces of terror, instability, division, and hate begin a deliberate campaign to disrupt our efforts, we stand ready to apply the capabilities required to thwart them, he said in a roughly eight-minute statement his first extended public remarks since taking office.

The withdrawal plan falls short of Trumps oft-repeated vow to end Americas long wars. It also runs counter to his guidance that troop withdrawals be based on the conditions on the ground, not a date on the calendar.