The agreement received warm endorsement in the United States from Congressmen of both parties. Thomas P. O'Neill (D-Mass.), Speaker of the House, said yesterday, "I think it's a tremendous achievement, locking those two fellas up like that and trying to hammer out something."

O'Neill added, "I'd be surprised if his [Carter's] image doesn't take off and go up 20 to 25 points."

Sen. Robert Byrd (D-W.Va.), the majority leader of the Senate, said Carter deserves the credit for "one of the most significant achievements in modern diplomatic history."

Carter, Begin and Sadat reached an agreement on the basic principles for a peace settlement late Sunday night. The framework includes provisions for a five-year transition period in which Israel would withdraw from the West Bank and Gaza.

Sadat and Begin also agreed to negotiate a peace treaty within the next three months, providing for Israeli military withdrawl from the Sinai, full exercise of Egyptian sovereignty there, and the establishment of diplomatic relations between Egypt and Israel. The Sinai provisions also include the return of Sinai airfields to Egyptian civilian control.

Adminstration officials emphasized on Sunday that the documents were not a completed set of agreements, but rather a "framework for continuing negotiations."