Iran accused Iraq today of new attacks on Iranian border villages and a leading religious figure resurrected Tehran's claim to the Persian Gulf state of Bahrain, underscoring Iran's increasing isolation in the region.

Iran's relations with Afghanistan are strained and there are increasing signs of eroding ties with the Soviet Union, Iran's powerful northern neighbor.

Iran's state-run radio said today that two Iraqi warplanes strafed at least three villages in western Iran and that Iraqi troops fired on another town from across the border. The radio made no mention of casualties.

Iran earlier accused Iraq of bombing and strafing several villages in Iran's Kurdish region June 4, reportedly killing seven people. That alleged attack aggravated already deteriorating relations between the two countries and escalated a war of words that now shows signs of engulfing other Arab states.

Certain to fuel the growing hostility between Arab gulf states and Iran's Islamic republic was statement by a senior figure in the entourage of Ayatollah Ruhollah Khomeini denouncing the previous government's renunciation of Iran's claim to Bahrain.

Ayatollah Sadegh Rouhani said the parliament that renounced the claim in May 1970 was illegal.

Rouhani mentioned the Arab sheikdom's former ties to the Persian Empire in arguing that Bahrain was still an Iranian "province." He said it would be considered as such "until its position is clarified by a national Islamic assembly."

Rouhani's remarks, while provocative to neighboring Arabs, appeared to be less a threat to actually take back Bahrain than a defensive response to Arab demands that Iran give up three Persian Gulf islands it seized in 1971.

Iranian-Arab relations began to deteriorate two weeks ago when government officials accused Iraq of stirring unrest among autonomy-seeking Arabs in the main oil-producing province of Khuzestan. Officials also charged that Kuwaiti radio broadcasts were encouraging the Arabs to rebel and claimed that radical Palestinian guerrilla leader Geroge Habash had been sighted in the province.

Shortly afterward Iraqi planes, apparently chasing Kurdish grerrillas across the border, struck Iranian villages near the town of Sardasht. Iran protested the attack and later said that Baghdad apologized for it, although this was denied by Iraqi officials in Tehran.

It seems unlikely, however, that Iran's protests would go beyond a war of words for the moment.

Military sources in Tehran said that while Iran's ragtag postrevolutionary Army still maintains a fairly complete armored division - including 200 Chieftain tanks - at the Khuzestan provincial capital, Ahwaz, its armed forces are in no shape to take on the Iraqis.

"Militarily speaking it would be nothing for Iraq to just destroy Iran," a foreign military attache said. In a rull-scale war, he added, "the Iranians wouldn't even be able to find their ammunition and spare parts."

Earlier this week official Iranian news media reported large antigovernment demonstrations in the Iraq holy city of Najaf, where Ayatollah Khomeini spent 15 years in exile before being expelled last fall. Iran said the demonstrations were to protest the detention of Ayatollah Mohammed Bagher Sadr, the leader of Khomeini's fellow Shiite Moslems in Iraq.

Khomeini subsequently sent a telegram to Sadr expressing regret over his treatment by "Iraqi agents" and obliquely warning that the Baghdad authorities could face the same fate as the deposed shah if they provoked the country's Shiites.

That and a series of anti-Iraqi demonstrations in Tehran apparently struck a raw nerve in Baghdad, and the official press warned Iran that "whoever plays such a game must pay dearly, for the Iraqi revolution has a more powerful and longer arm than they think."

Iran's relations with the Soviet Union also seem to be slippling, largely because of Moscow's role in helping Afghanistan's Communist leaders fight Moslem rebels.

In a series of terse exchanges with the Soviet ambassador to Iran this week, Khomeini also warned the Soviets not to interfere in Iranian affairs by supplying factions with weapons.

"We want Afghanistan, which is an Islamic country, to solve its problems through Islamic means," Khomeini told Ambassador Vladimir Vinogradov, according to Iranian radio.

"The interference of the Soviet Union there will also have an effect in Iran." he said. Khomeini charged that 50,000 Afghan Moslems have been killed by the pro-Moscow government in Kabul.

Vinogradov called the rebels "counterrevolutionaries" and asserted that the Afghan government had introduced beneficial reforms. CAPTION: Picture, Iranians outside Iraqui Embassy in Tehran protest alleged attacks on villages. AP; Map, no caption, By Dave Cook-The Washington Post