On a visit to the United States, Nazif met Bush in the White House on Wednesday.
"He commended us on the economic progress that took place in the country. He urged us to move ahead on the political reforms. He commended President Hosni Mubarak's move for the change of the constitution and urged us to make sure that the elections will be free and fair," Nazif said after the meeting.
Nazif also conferred with Secretary of State Condoleezza Rice on the first official solo visit to Washington by an Egyptian head of government.
US officials were pressing for clarification of new rules adopted by the Egyptian parliament providing for competitive presidential elections after a quarter century of unopposed rule by Hosni Mubarak.
Egypt's opposition called for a boycott of a 25 May referendum on the reform, saying the proposed change was filled with restrictions that would make it difficult to challenge Mubarak.
The United States has been pressing its Middle East ally for democratic reform, and State Department spokesman Richard Boucher said again on Tuesday that "we welcome the announcement of multi-party elections".
"We think that's important," he said. "And we think it's important to take it all the way and make it really happen."
But Boucher stressed the US commitment to see open and fair elections in Egypt and said the administration was "very aware" of opposition criticisms of the new rules.
Boucher said the US was pushing
Egypt for democratic reform
"We'll have an opportunity during the course of the next two days to understand better what the plans and intentions are of the Egyptian government and see how they plan to meet some of these criticisms."
Boucher would not comment on the Egyptian opposition allegations that the new system was a sham. "We don't sit here in judgment," he said.
"We sit here trying to move things forward, trying to make progress on reform, trying to make progress on democracy ... and support, where we can, efforts at real reform."
Bush has called for international observers during the September election.