Story highlights The defense secretary will now have the authority to decide troop levels in Afghanistan

The Trump administration already delegated authority for official troop levels in Iraq and Syria to Mattis

Washington (CNN) Secretary of Defense James Mattis confirmed Wednesday that President Donald Trump has given him the authority to make decisions about how many US troops are deployed to Afghanistan without first having to get formal agreement from the White House.

"At noon yesterday, President Trump delegated to me the authority to manage troop numbers in Afghanistan," Mattis told the Senate Appropriations Committee during a hearing on the Pentagon's budget request.

"The delegation of this authority, consistent with the authority President Trump granted me two months ago for Iraq and Syria, does not at this time change the troop numbers for Afghanistan," Mattis added.

"This assures the department can facilitate our missions and nimbly align our commitment to the situation on the ground," he said of the new authority.

"Our overall mission in Afghanistan remains the same, to train, advise and assist the Afghan forces so they can safeguard the Afghan people and terrorists can find no haven in Afghanistan for attacking us or others," Mattis said, saying the new strategy for Afghanistan will be presented to Trump in the "coming weeks."

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