The White House announced yesterday that U.S. and Soviet representatives will convene in Geneva next week to discuss President Reagan's decision to stop observing SALT II treaty limits on strategic nuclear weapons, but sources said there was still disagreement within the administration over what the U.S. position should be at the meeting.

The announcement by White House deputy press secretary Edward P. Djerejian, echoing unofficial reports earlier this week, said the United States had agreed to a Soviet request for a special session of the U.S.-Soviet Standing Consultative Commission (SCC). A senior White House official said the meeting is expected to last two weeks and that the U.S. delegation will be headed by retired general Richard H. Ellis, former chief of the Strategic Air Command and the U.S. member of this commission.

An administration source said the president's instructions to Ellis, which will set limits on what he can say, are being debated.

The internal disagreement over the U.S. approach to the meeting reflects a deeper conflict between the State Department and the Pentagon over how to deal with the Soviets on arms control issues. Sources said that the Defense Department looks upon the meeting as a Soviet "propaganda move" while the State Department sees it as an opportunity for a "productive exchange" that could provide momentum for a new strategic arms control pact.

"It has no purpose other than to keep the spotlight on a U.S. decision that Moscow thinks is unpopular in the rest of the world," said a U.S. official who wants the administration to stress Soviet violations of SALT II as the cause of the president's decision.

But an official who favors a more positive approach said that U.S. negotiators, after mentioning Soviet violations, could stress Reagan's desire for interim retraints leading to an agreement to make "significant reductions" in nuclear arsenals.

Djerejian said the meeting is expected to begin next Tuesday. He said U.S. representatives will be prepared to respond to Soviet concerns about Reagan's May 27 statement that the United States may exceed limits of the unratified SALT II treaty later this year. He said the Soviets are expected to respond to U.S. charges of Soviet noncompliance with arms control agreements.

"This special session of the Standing Consultative Commission offers us the opportunity to renew the president's request that the Soviet Union join us in establishing an interim framework of truly mutual restraint," Djerejian said.

The disagreement over the position that the U.S. should take at the SCC meeting has been aggravated by a running dispute between Ellis and Assistant Secretary of Defense Richard N. Perle.

Perle has charged that Ellis in the past has exceeded his instructions in trying to reach unauthorized compromises with Soviet representatives over alleged arms treaty violations. Ellis has argued that the SCC was designed to reach solutions rather than simply hear complaints. But at the last two sessions of the SCC, Perle has succeeded in limiting Ellis' instructions to prevent him from negotiating.

Perle and others have sought to reshape the staff of the U.S. delegation to the SCC with personnel more sympathetic to their point of view. Ellis has been given a new deputy commissioner, Stephen R. Hanmer Jr., who until recently served as a deputy to Perle.

In another move, Frank DeSimone, a longtime Ellis ally and executive secretary of the delegation, was replaced when his contract expired. Kenneth L. Adelman, director of the arms control agency and a Perle supporter, named Air Force Col. Bruce Clark as DeSimone's replacement.