Washington ? A senior associate of Osama bin Laden who is on President Bush’s most wanted list of international terrorists for allegedly helping plan the 1998 bombings of two U.S. embassies in east Africa has been captured in Sudan, senior administration officials said.

U.S. officials have been negotiating for more than a month with the Sudanese government to have Abu Anas Liby transferred to Egypt because he also allegedly took part in planning an attempted assassination of President Hosni Mubarak in June 1995, according to an official familiar with the negotiations.

Liby is the most senior al-Qaida member to be arrested since the United States launched its war on terrorism. He is the first person captured alive among the administration’s group of most wanted terrorists, a roster of 22 names released on Oct. 10.

U.S. authorities have a warrant for Liby’s arrest but appear willing to have him transferred to Egypt, citing his alleged participation in the attempt on Mubarak’s life, which took place before the embassy bombings. However, another practical reason is that Egyptian security officials are not bound in interrogation of prisoners by the same rules that apply to U.S. law enforcement agents.

Liby’s arrest was first disclosed in the Sunday Times of London. It reported he was one of nine terrorists arrested by the Sudanese government last month and is currently the subject of discussions with U.S. officials.

A CIA spokesman said he would not comment on the matter.