A man who prosecutors say received military training in Yemen from Anwar al-Awlaki, the American-born radical Muslim cleric who was later killed by the United States in a drone strike, pleaded guilty on Friday in Manhattan to three terrorism-related counts.

In 2010, prosecutors have said, the defendant, Minh Quang Pham, traveled secretly to Yemen, swore allegiance to Al Qaeda’s affiliate there and also helped the group prepare its online propaganda publication, Inspire.

Mr. Pham was extradited to the United States from Britain about a year ago and was scheduled for trial on Feb. 1 in Federal District Court in Manhattan.

But on Friday, he pleaded guilty to providing material support to the terrorist group — Al Qaeda in the Arabian Peninsula, or A.Q.A.P. — which carries a maximum prison term of 15 years; conspiring to receive military-type training from the group, for which he could face five years; and using a firearm in furtherance of crimes of violence, which carries a maximum life prison term and a mandatory minimum of 30 years.