All remaining issues considered significant by the United States in the strategic arms limitation treaty (SALT) talks have been resolved, and the two superpowers have begun concrete planning for a summit in Europe next month, administration sources said yesterday.

Secretary of State Cyrus R. Vance and Soviet *ambassador Anatoliy F. Dobrynin held two private negotiating sessions yesterday, reportedly moving for the first time from substantive SALT issues to consideration of the summit meeting between President Carter and Soviet President Leonid I Brezhnev.

Swedish radio in Stockholm said yesterday the summit would take place in the Swedish capital from June 13 to 15. Carter administration sources said this report was premature, but said Stockholm and that week of June were both possibilities.

"No site has been agreed to yet," one official said last night.

Senior administration officials said last night such an announcement that the talks are complete and that a summit was scheduled could come any time from today onward, and was likely by the end of this week at the latest.

Senior officials have been debating whether to announce an agreement in principle on the terms of SALT between Vance and Dobrynin, or whether to wait and couple that announcement with a firm schedule for a summit meeting.This is still not decided apparently.

In either case, the two countries' SALT negotiators in Geneva will need two to three more weeks of work on final treaty language and other details before the text of the pact can be made public.

The fact that Vance and Dobrynin began discussing the summit yesterday, and held two separate meetings in the course of the day gave rise to speculation that a final announcement was at hand. The second meeting late yesterday lasted just 11 minutes.

Between those two meetings yesterday, Vance met at the White House with President Carter, his principal aide Hamilton Jordan, and national security adviser Zbigniew Brzezinski to discuss SALT.

The White House-led SALT task force also met at the White House yesterday afternoon, but participants were not told that an announcement was imminent.

A middle-ranking Soviet official said in Washington yesterday that the new accord, known as SALT II, would be an important turning point in Soviet-American relations that could lead to a general improvement in the diplomatic atmosphere.

Georgi Arbatov, director of the Soviet Institute on the U.S.A. and Canada and an adviser to Brezhnev, said he and other Soviets would be willing to make the Soviet case for the treaty in the United States if asked to do so by appropriate Americans.