Soviet leader Mikhail Gorbachev arrived here today to attend the East German communist party congress, a meeting where he is expected to clarify his still-unfocused leadership of the East Bloc countries, and to emphasize changes in inter-European relations.

Analysts believe the Soviet leader may use the occasion to further define Moscow's position on such issues as the aggressive pursuit by the seven members of the alliance of improved economic and political ties with the West.

In particular, Gorbachev's presence has helped focus attention on contacts between the two Germanys. The congress, which Gorbachev will address on Friday, is expected to endorse the leadership of 73-year-old East German leader Erich Honecker.

Honecker has appeared close to going ahead with a twice-canceled visit to West Germany this year. Some analysts, however, believe prospects for the trip have been dimmed by Bonn's participation in the U.S. Strategic Defense Initiative and the recent rise in Soviet-American tensions.

Gorbachev is also expected to speak to the various approaches in the region to reforming the socialist system, but to avoid suggesting major changes in the policies that have produced the East Bloc's strongest economic performance in recent years.

Gorbachev's activity today was clearly meant to attract attention to his visit and, in turn, to his upcoming address.

After arriving by plane from Moscow this morning, he embarked on a day-long tour of the city marked by unusual public visibility and media-oriented spontaneity.

Trailed by two busloads of security men and a fleet of speeding autos, Gorbachev laid wreaths at three monuments, stopped at a hospital, a housing project and a concert hall, and climbed on a platform at the Brandenburg Gate to gaze over the Berlin Wall at West Berlin.

Despite the heavy security, a seemingly relaxed, smiling Gorbachev was quick to mix with crowds assembled at his stops. At one point he and a young boy tossed a ball back and forth.

The Soviet leader was flanked throughout most of the day by his wife, Raisa, who accepted and presented bouquets of flowers when Gorbachev was not laying wreaths.

At one midafternoon stop at the historic Schauspielhaus, a lavish concert hall in the city's center, Gorbachev listened to a brief Bach organ recital and heard a detailed report on the hall's decoration and post-World War II restoration. "We should achieve that all our managers are as knowledgeable about their fields," he remarked.

Also today, the Warsaw Pact military alliance declared that the U.S. air raid on Libya would "inevitably have negative effects on the situation in Europe."

The statement said the attack "will lead to an uncontrollable escalation of world tension."