MOSCOW, SEPT. 8 -- Key political figures from Iran and Iraq convened here today for separate meetings with Kremlin officials, dramatizing the increasing importance the opposing parties attach to Moscow's role as a mediator and counterweight to the United States in the gulf war.

Iranian Deputy Foreign Minister Mohammed Larijani, who arrived in the Soviet capital yesterday, held talks today with Foreign Minister Eduard Shevardnadze and Premier Nikolai Ryzhkov.

In both sessions, Larijani discussed Iran's position in its seven-year military conflict with Iraq, according to diplomatic sources.

Larijani also met with First Deputy Foreign Minister Yuri Vorontsov, who recently shuttled between Baghdad and Tehran in a diplomatic effort to lobby an end to the war.

Iraqi Foreign Minister Tariq Aziz arrived here today with a delegation of the seven-member Arab League for two days of meetings that are also expected to center on the Iran-Iraq war, the official news agency Tass reported.

Besides the meetings of the Arab League, led by Kuwaiti Foreign Minister Sabah Ahmed Sabah, Aziz is expected to hold separate consultations with Soviet officials, diplomatic sources said. But a direct meeting between Iraq's Aziz and Iran's Larijana is doubtful, they said.

As United Nations Secretary General Javier Perez de Cuellar prepares to launch a new effort to enforce a cease-fire in the war, both sides seem to be using Moscow as the venue for jockeying for a position, diplomatic sources here said.

With U.S.-Iranian relations severely strained in the wake of the Iran-contra affair, and Iraq heavily dependent on Soviet arms supplies in the war, both sides are "leaning more and more toward Moscow as a broker," a western diplomat said here today.

One reason is that the Soviet Union plays a unique role as a major world power that maintains good relations with both warring parties.

Iran, Iraq and the Soviet Union also seem to share an interest in limiting the Reagan administration's involvement in the region, Moscow-based diplomats said. Already, Iran and the Soviet Union have made a joint call for an end to the U.S. military buildup in the gulf.

Following today's meeting between Shevardnadze and Larijani, Soviet Foreign Ministry spokesman Gennadi Gerasimov told reporters that "both sides agreed that the imperialist presence in the Persian Gulf favors only the United States and they stated their interest is the speediest possible removal of the naval ships from that region."

Ryzhkov and Larijani buttressed the point.

They "expressed serious concern over an unprecedented buildup of the military presence of the U.S. and its allies in the Persian Gulf zone, which was at variance with the interests of international security and of independent development of the countries of that region," a Tass dispatch said about the meeting between the Soviet prime minister and the Iranian deputy foreign minister.

For its part, Moscow is apparently using close diplomatic links to Tehran and Baghdad to cajole both sides into a cease-fire, stressing the United Nations resolution calling for a cease-fire passed in July and the upcoming visit of Perez de Cuellar.

It thus hopes to avoid more forceful measures that might result in strained relations.

In his meeting with Larijani today, Ryzhkov "emphasized the importance of {the resolution's} early implementation," Tass reported.

"Attention was drawn to the need for cooperating with the United Nations secretary general in the exercise of his mission and his mediatory efforts to attain the goals formulated in the security council resolution," Tass also said.

The Soviet Union is said to oppose the use of economic sanctions against the two countries to force a cease-fire. Such a move would likely cripple Iraq, which Moscow has long supplied with weapons in the war, and would also counter Soviet efforts to beef up its economic ties to Iran, which include plans for Moscow to buy natural gas from Tehran.