Kohl Seeking to Reassure Soviets : Europe: West German chancellor is expected to promise expanded trade at meeting with Gorbachev.

His pockets laden with concessions gathered at three recent Western summit meetings, West German Chancellor Helmut Kohl arrived here late Saturday for two days of pivotal talks with Soviet leader Mikhail S. Gorbachev aimed at removing the final barriers to German reunification.

During meetings here and in Gorbachev’s home Caucasus region, Kohl hopes to provide the Soviet leader with enough help to break stiff resistance among Soviet conservatives. The conservatives are unsettled by the prospect of a united Germany and are vehemently opposed to its membership in the North Atlantic Treaty Organization.

No specific agreements are expected to be signed during the visit, but West German promises of expanded trade and Western help for Soviet economic reform are expected to ease Moscow’s concerns.

During the trip, Kohl is expected to lay the groundwork for a formal treaty next year that would serve as the cornerstone of relations between the Soviet Union and a united Germany.

West German officials also said Kohl will likely discuss the military strength of a united Germany.

Kohl, East German Prime Minister Lothar de Maiziere and West Germany’s Western allies all advocate membership in NATO as the best way to anchor a united Germany in the West and prevent the emergence of an independent German military command.

Important issues linked to German unity remain to be addressed in ongoing negotiations between the four World War II victorious powers--the United States, Britain, France and the Soviet Union--and the two Germanys. However, Soviet consent on the issue of NATO membership is considered the biggest obstacle.

German-Soviet agreement on the terms of German unity is considered vital for the future of Europe in general and for what arguably will become the Continent’s most important bilateral relationship. This is so even though the pace of unification has accelerated so quickly and gathered such domestic political momentum in recent months that most Western analysts question whether Moscow can block it.

The fact that more than half the 50 million World War II dead fell in fighting between Germany and the Soviet Union has loaded the two nations’ relationship with emotion.

The extent to which Kohl has pushed his Western partners and offered bilateral assistance to Moscow is a measure of the importance that the Germans place on winning Soviet approval.

Among Kohl’s recent diplomatic successes:

* With the help of French President Francois Mitterrand, he managed to override doubters at a 12-nation European Community summit last month in Dublin and win agreement in principle to provide economic aid to the Soviet Union. Although he failed to get an immediate $15-billion aid package, EC leaders agreed to meet again in October to discuss specifics.

* Just over a week later, this time working closely with President Bush at an alliance summit in London, Kohl helped push through major changes in NATO strategy that were tailor-made to Soviet liking.

These included the softening of the alliance’s nuclear doctrine by declaring nuclear forces to be “weapons of last resort,” a proposed joint declaration of nonaggression with the nations of the Warsaw Pact and an invitation to Gorbachev to visit the alliance headquarters.

Mitterrand and British Prime Minister Margaret Thatcher were said to be dismayed by the extent of the concessions, but Moscow was distinctly pleased.

“Now we can tell those grumbling generals that they are wrong,” Foreign Ministry spokesman Gennady I. Gerasimov said when informed of the changes.

In an extremely important concession, Kohl also agreed at the NATO summit to limit the size of a united German military force before reunification occurs.

(NATO Secretary General Manfred Woerner, in Moscow on Saturday to brief Gorbachev and Foreign Minister Eduard A. Shevardnadze on the NATO changes, declared that the alliance no longer views the Soviets as an enemy, Southwest German Radio reported.)

* Last week, at the seven-nation Houston economic summit, Kohl broke down stiff U.S. and Japanese resistance to avoid outright rejection of aid to the Soviet Union. Instead, he won a formal endorsement that Gorbachev’s reforms “deserve our support,” along with a study of Soviet reforms and recommendations on how Western aid might help.

Shevardnadze labeled the summit declaration “an important step forward.”

In addition to these multilateral measures, Kohl’s government so far this year has guaranteed a $3-billion credit line to the Soviet Union, organized by a German-led bank consortium. It has also provided $140 million in food aid and agreed to pay $780 million for the cost of stationing Soviet troops in East Germany for the balance of the year.

A senior Kohl aide said Friday that Bonn plans to offer no more financial help to Moscow.

“There are no presents in our luggage,” this aide said.

But the fact that West German Finance Minister Theo Waigel is accompanying Kohl to Moscow indicates a strong economic and trade dimension to the trip.

Chancellery officials spoke of “a complex of possible bilateral projects,” including West German assistance in areas such as product marketing and other areas of consulting.

West Germany is already the Soviet Union’s largest Western trading partner; East Germany has long been Moscow’s premier foreign supplier of machine tools and such items as high-technology optics.

Few countries can offer Moscow more experience or the technical know-how to support its planned package of radical reforms than can a united Germany.

On the political front, Kohl and his foreign minister, Hans-Dietrich Genscher, have coupled their insistance for German NATO membership with a pledge renouncing the development of nuclear, chemical or biological weapons and agreeing to limit the size of a united German military force.