The United States conducted a "successful" counterterrorism operation against a "significant" Al Qaeda leader Ayman Al Zawahiri in Afghanistan over the weekend, a senior administration official told Fox News.

President Biden on Monday night at 7:30 p.m. E.T. is expected to address the nation from the White House on the operation.

"Over the weekend, the United States conducted a counterterrorism operation against a significant Al Qaeda target in Afghanistan," the senior administration official told Fox News Monday. "The operation was successful and there were no civilian casualties."

Two intelligence sources tell Fox News Al Qaeda leader Ayman Al Zawahiri was killed in the CIA drone strike.

BIDEN ADMIN WARNED NOT TO WITHHOLD AFTER-ACTION REPORTS ON BOTCHED AFGHANISTAN WITHDRAWAL

The Biden administration closed the U.S. Embassy in Kabul and withdrew all military assets from Afghanistan on Aug. 31, 2021, ending the United States' longest war.