VIENNA, JUNE 14 -- NATO and Warsaw Pact representatives announced today that they are close to agreement on cuts in tanks and other armored vehicles each side can station in Europe, which -- if last-minute Soviet questions are resolved -- would be a breakthrough toward completing a treaty on conventional forces by the end of this year.

The chief negotiators of France and Poland, who worked out the deal, called it an important step forward at the 23-nation talks on Conventional Forces in Europe. The negotiations have stagnated for eight weeks, with members of the Western alliance voicing concern that the Soviet Union was stalling.

Proposals by East and West have coincided in recent months on limiting to 20,000 the number of tanks each alliance can retain, but thorny questions of definitions and weight categories have thwarted substantive progress on key elements of the treaty.

"This result is in my opinion a breakthrough from which we expect a stimulus for the other areas of negotiations," French Ambassador Francois Plaisant told a news conference. The package was presented at a morning session, where no objections were raised.

"This settlement signals substantial progress at the Vienna negotiations," chief Soviet delegate Oleg Grinevsky said. But at an afternoon negotiating session, the Soviet Union withheld final approval of the text pending clarification on equipment involved, according to senior Western delegates.

A spokesman for the Soviet delegation said he was unaware of any problem over acceptance of the package and the Western diplomats expressed hope that the text would be adopted in the coming days.

The United States and its allies argue there is no point in holding the planned December gathering of leaders of the 35 member states of the Conference on Security and Cooperation in Europe before an arms treaty has been reached.

NATO foreign ministers pledged to intensify efforts at reaching an accord when they met in Turnberry, Scotland, last week. The French-Polish package was submitted after Soviet President Mikhail Gorbachev offered a compromise on tank weight parameters at the summit meeting in Washington, diplomatic sources said.

Under the package, the 20,000-tank ceiling will apply to those weighing 16.5 tons or more unloaded, halfway between earlier NATO and Warsaw Pact positions. Both wheeled and tracked tanks will be covered. By far the largest cuts would be borne by the Soviet Union, which would have to rid itself of as many as 35,000 tanks, depending on the pace of its unilateral withdrawals from Eastern Europe. Armored infantry combat vehicles would be limited to 18,000 on each side, with a minimum weight of six tons.

Weight parameters have been in heated dispute because of Soviet concern that the West could benefit from technological leaps and develop light-weight tanks in circumvention of the treaty. There were also disagreements among some members of the two blocs over which of their tank models would be discarded, but these now appear resolved.

"We have much to do, but we hope that this step forward will help us to accelerate the pace," said Polish Ambassador Wlodzimierz Konarski. Both sides remain far apart on the ceilings for combat aircraft and helicopters, as well as on verification and on whether decommissioned tanks should be destroyed or converted for nonmilitary use.

Another obstacle is how and when to include troop cuts beyond those involving U.S. and Soviet forces stationed in Europe. The Soviet Union and some other Eastern states are pressing for additional personnel limitations in the Central European region out of concern over the size of a united German army.