Soviet diplomats, in an unusual news conference at their embassy here yesterday, called for new East-West negotiations to discuss reductions of conventional and tactical nuclear forces in Europe "from the Atlantic to the Ural Mountains."

The call for new arms-control talks was based, they said, on ideas presented April 18 by Soviet leader Mikhail Gorbachev in East Germany.

Gorbachev said then that the Soviet Union was prepared to meet concerns of West Europeans, who said elimination of U.S. and Soviet medium-range missiles in Europe, now under discussion in Geneva, would leave Moscow with an advantage in conventional forces.

State Department spokesman Charles E. Redman said yesterday that, when Gorbachev first made his remarks, it was not clear whether he "was proposing a new set of negotiations or an expansion of the talks already under way."

Redman added that "our first priority is to negotiate radical reductions in strategic and intermediate-range nuclear weapons." In the latter talks, he said, the United States proposes a freeze on tactical nuclear arms.

Redman said parts of the still vague Soviet proposal appeared to cut across the Geneva nuclear negotiations, 10-year talks in Vienna that deal with reducing North Atlantic Treaty Organization and Warsaw Pact conventional forces, and the Stockholm discussions aimed at European confidence-building measures.

The Stockholm talks resumed April 15, while the Geneva negotiations are due to resume May 8 and the Vienna talks May 18.

Sergey Kislyak, an embassy first secretary specializing in arms-control matters, told reporters yesterday that Gorbachev wants to go beyond existing Vienna negotiations with what Kislyak termed a "new, bold approach" that would include tactical nuclear forces and troops from all European nations.

The reductions, he said, would start with troops of the two alliances and eventually include other European powers.

He denied that the purpose of this initiative was propaganda or an attempt to drive a wedge between the United States and NATO allies.

Saying the proposal has been delivered to "appropriate channels" of the U.S. government, embassy second secretary Vitaly Churkin said Moscow hopes for "serious consideration" by Washington but has "not proposed a particular forum" for the talks.