U.S. Defense Secretary Lloyd Austin said Thursday the al-Qaida extremist group that used Afghanistan as a staging base to attack United States 20 years ago may attempt to regenerate there following an American withdrawal that has left the Taliban in power.

Austin spoke to a small group of reporters in Kuwait City at the conclusion of a four-day tour of Persian Gulf states. He said the United States is prepared to prevent an al-Qaida comeback in Afghanistan that would threaten the United States.

"The whole community is kind of watching to see what happens and whether or not al-Qaida has the ability to regenerate in Afghanistan," he said. "The nature of al-Qaida and (the Islamic State group) is they will always attempt to find space to grow and regenerate, whether it's there, whether it's in Somalia, or whether it's in any other ungoverned space. I think that's the nature of the organization."

The Taliban had provided al-Qaida with sanctuary while it ruled Afghanistan from 1996 to 2001. The U.S. invaded and overthrew the Taliban after it refused to turn over al-Qaida leaders following the Sept. 11, 2001 attack on the United States. During the course of the 20-year U.S. war, al-Qaida was vastly diminished, but questions have arisen about its future prospects with the Taliban back in Kabul.

"We put the Taliban on notice that we expect them to not allow that to happen," Austin said, referring to the possibility of al-Qaida using Afghanistan as a staging base in the future.

In a February 2020 agreement with the Trump administration, Taliban leaders pledged not to support al-Qaida or other extremist groups that would threaten the United States. But U.S. officials believe the Taliban maintain ties to al-Qaida, and many nations, including Gulf Arab states, are concerned that the Taliban's return to power could open the door to a resurgence of al-Qaida influence.

Austin has asserted that the U.S. military is capable of containing al-Qaida or any other extremist threat to the United States emanating from Afghanistan by using surveillance and strike aircraft based elsewhere, including in the Persian Gulf. He also has acknowledged that it will be more difficult without U.S. troops and intelligence teams based in Afghanistan.

Austin and Secretary of State Antony Blinken appeared together in Qatar on Tuesday in a show of U.S. gratitude for that Gulf state's help with the transit of tens of thousands of Afghans and others evacuated from Kabul. Blinken also visited an evacuee transit site in Germany, and Austin visited Bahrain and Kuwait.

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