WASHINGTON  The Obama administration is discussing with Egyptian officials a proposal for President Hosni Mubarak to resign immediately and turn over power to a transitional government headed by Vice President Omar Suleiman with the support of the Egyptian military, administration officials and Arab diplomats said Thursday.

Even though Mr. Mubarak has balked, so far, at leaving now, officials from both governments are continuing talks about a plan in which Mr. Suleiman, backed by Lt. Gen. Sami Enan, chief of the Egyptian armed forces, and Field Marshal Mohamed Tantawi, the defense minister, would immediately begin a process of constitutional reform.

The proposal also calls for the transitional government to invite members from a broad range of opposition groups, including the banned Muslim Brotherhood, to begin work to open up the country’s electoral system in an effort to bring about free and fair elections in September, the officials said.

Senior administration officials said that the proposal was one of several options under discussion with high-level Egyptian officials around Mr. Mubarak in an effort to persuade the president to step down now.