A key White House aide said yesterday the Carter administration wants to rework the controversial Bermuda II agreements to make air services between the United States and the United Kingdom more competitive.

Simon Lazarus, associate director of the White House domestic policy staff, said the United States will begin pressing later this month for major changes in the agreement to allow more American carriers to fly nonstop to Great Britian from more U.S. cities and to give airlines more freedom to set their own prices without governmental interference.

Ongoing consultations on the agreement begin later this month in London, Larzarus noted in a speech to the International Aviation Club.

Provisions of Bermuda II, the first major air services bilateral agreement signed by the Carter administration, have been attacked in the past couple of years for failing to promote the kind of pro-competitive international aviation policy the president has supported. For instance, while the United States has sought to sign agreements with other countries that allow this country to name as many airlines to fly a route as want to go, the U.S.U.K. pact limits most routes to just one U.S. airline.

Under Bermuda II, in fact, one U.S. airline had to stop serving the Boston-London route.

In his remarks yesterday, Lazarus, who makes recommendations to the president on international rate and route matters, contended that British Prime Minister Margaret Thatcher shared President Carter's convictions about reduced government intervention.

He quoted statements she had made about her belief that "there can be no liberty unless there is economic liberty" and her preference for policies "based on consumer choice and fair competition, freer movement of capital and people."

"We doubt that there is any area where the case for implementing this shared philosophy is more clear than the case of air service between Great Britian and the United States," Lazarus said.

Lazarus and other U.S. aviation officials cite recent British airline applications for new services and apparent British Aviation Authority receptivity to them as reasons for optimism that the British might go along with a liberalization of the agreement. For instance, Britian's Civil Aviation Authority recently granted British Calendonian Airways authority to fly to St. Louis and Denver, two cities not listed in the agreement. The agreement would have to be expanded to allow such serivces.