NEW YORK, SEPT. 29 -- President Bush today asked Prime Minister Toshiki Kaifu for "timely" payment of the $4 billion Japan has promised to contribute to the Persian Gulf effort, but did not press for more funds or the commitment of more personnel, administration officials said today.

How much money Japan should commit to the effort to reverse Iraq's Aug. 2 invasion of Kuwait has become increasingly contentious in the United States. Japan originally pledged $1 billion, but increased that under intense U.S. pressure.

Bush and Kaifu met for nearly an hour today, the last in a series of mostly brief sessions Bush had with leaders attending the World Children's summit and U.N. General Assembly sessions. About 70 world leaders, including Bush, are to participate in Sunday's summit on the rights of children.

Assistant Secretary of State Richard Solomon said Bush asked Kaifu for "timely disbursement" of his commitments. A senior official said virtually all the other nations providing forces and aid to the gulf effort are disbursing it this year but Japan has not set a timetable or committed to a 1990 schedule.

Kaifu has pledged to send 100 volunteer medical workers to the region. He said earlier this month that he had asked his cabinet to develop a plan to send hundreds, perhaps thousands, more in some kind of unarmed support force in keeping with Japan's pacifist constitution.

Many elected officials in the United States have complained strongly that Japan's contribution has been insufficient. Japan has a large stake in the crisis, importing virtually all its oil, some 70 percent of it from the Middle East. Earlier this month, the House, reflecting growing anger with Japan, voted overwhelmingly to begin withdrawing 5,000 U.S. troops a year from Japan unless it pays the cost of the U.S. military presence there -- estimated at $7.4 billion a year.

Bush discussed the gulf situation in virtually all six sessions he held with foreign leaders today. The president will meet with more than 20 world leaders in three days of diplomacy here, in addition to addressing the children's summit and the General Assembly.

Colombia President Cesar Gaviria, who held a brief session with Bush, said the president thanked Colombia for increasing its oil production and for supporting U.N. actions against Iraq. "He has the hope that we will not have a war there," Gaviria said.

Gaviria described Bush as "very satisfied" with Colombia's drug policies, despite Gaviria's new policy of offering trials in Colombia to drug traffickers wanted in the United States and his reluctance to use more military muscle in the drug fight. According to the White House, Bush asked Gaviria to work on allowing "consensual boarding" of ships suspected of carrying drugs. Bush wants the U.S. Coast Guard to be allowed to inspect ships at sea off Colombia's coast.

Gaviria also said Bush has pledged to ask Congress to alter U.S. trade policies to give Colombian cut flowers special trade benefits.

National security adviser Brent Scowcroft, who said Friday the administration may seek new U.N. sanctions against Iraq that could include military action, today said Bush's meetings and U.N. address will focus on the international response to the Persian Gulf crisis.

Scowcroft said Bush will not seek new U.N. actions on this visit, but may do so later.

In a television interview to be broadcast Sunday, Soviet Foreign Minister Eduard Shevardnadze repeated that his nation would comply with any U.N. resolution calling for military action against Iraq. Asked if Soviet troops would serve in a U.N. force, Shevardnadze said on NBC's "Meet the Press" it is a "principle" that the Soviet Union will comply with any Security Council resolution. "And that would include anything regarding the involvement of the Soviet troops under the flag . . . of the United Nations," he said.

Bush is expected to focus his U.N. speech Monday on the gulf crisis, which has dominated this General Assembly session, and to cite the eight U.N. resolutions against Iraq as ushering in a new stage in which the United Nations can assume what Scowcroft called "more the place envisioned by its founders as a very important vehicle in maintaining world peace and tranquility.