With domestic and international attention increasingly focused on the new leader of the Soviet Union, Mikhail Gorbachev, world leaders began arriving here today for Wednesday's Red Square funeral of his predecessor, Konstantin Chernenko, who died Sunday at the age of 73.

Gorbachev's picture was on the front pages of today's Soviet newspapers, along with accounts of his acceptance speech yesterday to the Central Committee of the Communist Party after his rapid selection as party general secretary.

The announcement of Chernenko's death was at the bottom of the front page and his obituary and picture were on the second page of today's editions.

Vice President Bush, who arrived this evening along with Secretary of State George P. Shultz, said in an arrival statement that he would convey President Reagan's hopes for improved relations with the Soviet Union as Gorbachev takes charge.

In another indication of the major contacts to be pursued here this week, the leaders of East Germany and West Germany met here for more than two hours tonight and pledged to "develop and build good neighborly relations."

A blossoming dialogue between East Germany's Erich Honecker and West German Chancellor Helmut Kohl was cut short by Soviet pressure last year, forcing Honecker to cancel a planned visit to Bonn.

In his statement, Bush said: "We have no greater hope and no greater goal than to create a more stable and constructive relationship with the Soviet Union."

". . . We recognize that the United States and the Soviet Union do differ on many important questions," he said. "Nevertheless, we are ready to bridge those differences and we hope the new Soviet leader is equally committed to finding solutions to the problems that confront us."

Among the 30-member American delegation are Assistant Secretary of State Richard Burt, who joined Bush's party in Geneva, and Deputy Assistant Secretary Mark Palmer. Bush, who has attended the funerals of the two previous Soviet leaders in the last 28 months, hopes to meet with Gorbachev Wednesday afternoon.

Other dignitaries arriving for the funeral included leaders of East Bloc states, British Prime Minister Margaret Thatcher, French President Francois Mitterrand, Italian President Sandro Pertini, Indian Prime Minister Rajiv Gandhi, President Mohammed Zia ul-Haq of Pakistan and Japanese Prime Minister Yasuhiro Nakasone.

Bush is expected to meet with Zia, Kohl, Nakasone and perhaps others before leaving either Wednesday night or Thursday.

Bush, Shultz and U.S. Ambassador Arthur Hartman proceeded immediately from the airport to pay their respects at the Hall of Columns in the House of Unions where Chernenko's body has been lying in state since yesterday afternoon.

Preparations for Wednesday's funeral, which begins at 1 p.m. (5 a.m. EST), have gone ahead quickly and smoothly, reflecting the speed of the transition from Chernenko to Gorbachev.

After the deaths of Leonid Brezhnev and Yuri Andropov, their obituaries occupied the front pages, but in both cases, the succession in the leadership was not announced until the next day.

This time, the mourning period has been more subdued, the lying in state period shorter, and more attention -- both here and abroad -- is focused on the new leader who, at 54, is the youngest man to take charge in the Kremlin since Joseph Stalin took over in 1924 at the age of 45.

With the exception of Thatcher, who met Gorbachev last December during his week-long tour of Britain, this will be the first opportunity western leaders have had to meet privately with Gorbachev.

After Wednesday's funeral, which will begin with a procession bearing the body from the House of Unions, Gorbachev will attend a Kremlin reception for visiting dignitaries. He then will meet with visiting heads of state from East Bloc countries and with western leaders, although his schedule apparently has not yet been set.

Gorbachev and members of the leadership returned again at noon today to the Hall of Columns to pay respects to Chernenko and again conveyed condolences to Chernenko's wife, Anna, and other family members.

In addition to Bush and Shultz, other foreign dignitaries paying their respects included Canadian Prime Minister Brian Mulroney, Kohl and leaders from Eastern European allies of Moscow including Presidents Nicolae Ceausescu of Romania and Gustav Husak of Czechoslovakia and East Germany's Honecker.

All day today, streams of people filed through the 18th century building. They moved at a brisk pace past wreaths of flowers and lines of soldiers, slowing down once inside the hall where a full orchestra played classical music next to the bier decked with flowers and medals.

Busloads of mourners arrived in the center of Moscow, where passengers got out to form lines that snaked down a side street to the House of Unions.