Few Middle East crises of recent times have so caught Moscow in the crosscurrents of its own interests and vulnerabilities as the Persian Gulf war.

The consequences of the conflict -- economic, military, political -- reverberate with dismaying complexity for the Kremlin. The war offers unique opportunities for improved Soviet global position and regional influence, but it also threatens new anti-Soviet outbursts within the Islamic world that could further impair Soviet-Moslem relations already damaged by the invasion of Afghanistan.

Overshadowing these contradictions is the threat of a direct confrontation with the United States and the West over future access to crucial Persian Gulf oil supplies. The Soviet Leadership seems well aware that this danger grows with every day the fighting continues and the prospect of an early peace fades. Continued hostilities and turmoil in the strategic area could raise this peril to the flash point.

Moscow has called on Baghdad and Tehran to go to the negotiating table and warned the West against "external" interference. It also has denounced the idea of either a neutral peacekeeping force or any move by Washington and its allies to keep the Strait of Hormuz open by military means.

The areas for misunderstanding and miscalculation are thus already critically elevated. At the same time, however, Moscow is aware that the longer the hostilities continue, the greater the potential benefit to the Soviet Union -- as long as the great powers are not drawn into a confrontation.

By bombing and shelling each other's oil production facilities, Iran and Iraq have not only weakened their own economies, but may have given Moscow substantial long-term gains in its global contest with the West. Sharp reductions in the two nations' oil exports over a long period of time could bring grave worldwide economic consequences and possible political gain for the Kremlin.

Rapid depletion of the present world oil glut would lead to surging energy prices, renewed dislocations in Western economies and drive the East Europeans, already critically short of hard currency and facing major Western debts, further into Soviet economic domination.

While President Carter has said the United States is immune from immediate impact of the war because of a 100-day oil reserve, this is not true of all the allies. Well-informed sources here say that Turkey -- with only a 45-day reserve and its principal suppliers, Iraq and Iran, now shipping nothing -- is scrambling for alternate supplies from Libya.

Aside from forcing the Turks to increase their economic dealings with the anti-American Libyans, the situation has underscored Ankara's vulnerability despite its NATO membership.

Seeking to exploit the anti-American sentiments of Baghdad and Tehran, Soviet press commentaries during the week have blamed the conflict on the United States and warned that the war may provide Washington with an excuse to move back into the Persian Gulf in force. The Soviets also have said the conflict damages Arab unity in dealing with Israel.

As with its propaganda over the Afghanistan intervention, Moscow's charges against Washington represent a deliberate attempt to obscure the Soviet's own uncomfortable situation: the undeclared gulf war puts on official Soviet ally using Soviet weapons against a revolutionary regime whose anti-American stance already has brought Moscow immense gains.

The Soviets have further complicated their relations with the Moslem and Arab states by labeling Pakistani President Mohammed Zia ul-Haq a puppet of Washington and Peking. Even as the Islamic Conference chose Zia to lead a "good-will" mission to Tehran and Baghdad to see about peace possibilities, the official Tass press agency called Zia a U.S. lackey bent on "total militarization of the state despite its dire economic plight."

Moscow's 1972 friendship [Word illegible] with Iraq, the reason for continued Soviet arms shipments, is another complication. The pact was signed in the days when the Kremlin was desperate to limit the pro-Western shah's drive for undisputed domination of the gulf.

Now, in one of the ironies that abound in Soviet-Arab relations, Iraqi strongman Saddam Hussein, no longer so friendly to Moscow because of his country's economic independence, is using Soviet weapons to seek dominance of the gulf himself. But the Soviets cannot denounce him, however displeased they may be, for fear of the impact that would have in other Arab countries where Moscow seeks influence.

At the same time, military and economic blows to Tehran serve Moscow's interests, earning it friends in the largely Sunni Moslem Arab world for weakening Ayatollah Ruhollah Khomeini's call for the spread of minority Shite Islamic fundamentalism. And increased political turmoil in Tehran, certain to result from the war, improves the chances for Marxist subversion, raising hopes within the Soviet leadership for an eventual communist takeover there.

In such an eventuality, Moscow would undoubtedly stand ready to invoke the mutual defense clause of the 1921 Soviet-Iranian treaty.Khomeini abrogated the clause last year, but Moscow, with thousands of well-equipped troops near the Iranian border, has never accepted his move.

If that opportunity arises, the Kremlin will have to balance it against the danger of a certain confrontation with the West for control of Iran's oil. Thus does the Persian Gulf war offer gain and peril to this capital.