Iran asked the Soviet government today to stop arms shipments to Iraq and threatened to recall the Iranian ambassador here in a move reflecting a sharp souring of Moscow-Tehran relations.

Iranian Ambassador Mohammed Mokri told a press conference that "if the Soviet military assistance to Iraq does not end, I doubt if I shall be ambassador here for long."

The Iranian request places the Soviets in an awkward position, since they are obligated under a 1972 friendship treaty with Iraq to supply weapons to the Iraqi armed forces. The Soviets are known to have supplied Mig 23 jets, surface-to-air and surface-to-surface missiles to Iraq.

Iraq has been considered a major Soviet ally in the Arab world, but recently has shown signs of increasing independence.

Iraq and Iran have clashed periodically across their disputed border for the past five years. But hostilities between the two large oil-producing states have risen sharply in the last two years because of Iraqi support for restive ethnic Arabs and Kurds in Iran.

Mokri mentioned "tens of helicopters and aircraft" used by the Iraqi forces in what he termed "daily bombings of our frontier." He did not provide other details except to suggest that the weapons are used to support "counterrevolutionary" forces inside Iran.

While calling Soviet weapons shipments to Iraq an "unfriendly gesture," Mokri stressed that he hopes for a satisfactory response from the Soviet government.

On two previous occasions since last November, the Iranians publicly have deplored arms shipments to Iraq on grounds that the weapons were used to stimulate unrest among large minorities living in Iran along the Iranian-Iraqi border. Today's warning was the strongest to date and for the first time includes the threat of downgrading the Iranian diplomatic mission here.

The weapons issued has been souring Soviet-Iranian relations for some time. In June, the Iranians expelled a Soviet diplomat on espionage charges and asked the Soviets to reduce the size of their embassy staff in Tehran.

The Iranians have also been annoyed by Moscow's rejection of their request for increased river transit facilities inside the Soviet Union. Iran wanted to secure the use of the Soviet river and canal network that links the Caspian Sea with the Black Sea in an effort to circumvent an American trade boycott.

The Soviets in turn have been hurt economically by a cut in Iranian natural gas exports to the Soviet Union to only 15 percent of the 25 million cubic meters contracted under the shah.

Moreover, the Iranians are now asking a price five times higher than the previous one. Gas deliveries have been halted and negotiations remain stalled on the price issue.