The United States and the Soviet Union announced today that negotiations would begin in Geneva Nov. 30 on the limitation of medium-range nuclear weapons in Europe.

This was the first tangible result of what was termed a "quite positive" initial meeting of the countries' foreign ministers since the advent of the Reagan administration.

The three-paragraph statement was agreed upon yesterday by Secretary of State Alexander M. Haig Jr. and Soviet Foreign Minister Andrei Gromyko in talks described as covering a wide range of international issues.

Aside from today's joint statement on European arms control, which was issued simultaneously in Moscow and New York, the two men have said almost nothing in public about their four-hour meeting, nearly three hours of which was without advisers present.

Haig, however, was reported by informed sources to have told Western foreign ministers at a breakfast this morning that the session with Gromyko was "quite positive." Haig's aides refused to give details of the Gromyko session, partly on the ground that any comment might complicate the second of the two scheduled meetings, on Monday at the Soviet Mission to the United Nations.

U.S. diplomats had expected the agreement on a date and place for a formal start to the theater nuclear force negotiations to flow from the Haig-Gromyko meetings. Draft copies of a joint announcement had been exchanged between the two sides more than a week ago.

The text of the announcement as adopted, however, broadly suggested--and informed diplomats confirmed privately--that the two sides have not even agreed on what armaments are to be covered in the forthcoming negotiations.

According to the announcement, the negotiations are to concern "those nuclear arms which were discussed earlier between the U.S. and U.S.S.R. representatives in Geneva." This unusually vague wording, the sources confirmed, is intended to preserve the differing positions of the two sides on the scope of the talks. This was not resolved during informal Soviet-American discussions on the issue late last year.

The United States wants the negotiations to concentrate, at least initially, on Soviet SS20 multiple-warhead missiles, older Soviet SS4 and SS5 missiles, and new U.S.-built Pershing II and cruise missiles.

The Soviets say the negotiations should also take into account a range of other Western forces, generally known as "forward-based systems," such as nuclear-armed aircraft deployed in Western Europe and on U.S. aircraft carriers, as well as older U.S. ballistic missiles and nuclear forces of France and Britain.

Senior officials on both sides have acknowledged, moreover, that the European nuclear issues are closely tied to the greater problems of intercontinental nuclear weapons, the "central systems" covered by strategic arms limitation treaties.

A senior U.S. official recently said, "There is no possible way of separating the two" questions, even though he also said that theater and strategic negotiations technically will be separate. Soviet officials have told Western visitors they cannot envisage success in limiting European-based nuclear arms while the SALT process remains stalemated.

Perhaps the most serious problem for the newly announced negotiations is that the two sides seem to be seeking diametrically opposite results. The Soviets are believed to be pursuing the talks in hopes of forestalling the buildup in Europe of more powerful Pershing II and cruise missiles in the next several years.

The United States, on the other hand, sees the negotiations as a necessary step toward deploying these weapons because it obtained European willingness to base the new weapons two years ago by pledging to pursue such talks.

Today's announcement said the U.S. team at the negotiations will be headed by Paul Nitze and the Soviet side by U.A. Kvitsinsky.