Iran refused to allow the Iraqi prime minister to fly across its airspace as he was traveling to Tokyo, members of the delegation traveling with Nouri al-Maliki told The Associated Press early Sunday.

The delegation members said al-Maliki's plane was diverted on Saturday night to Dubai, United Arab Emirates, where al-Maliki stayed in the airport for more than three hours while his government aircraft was refueled and a new flight plan was filed.

Two members of the delegation told AP about the incident by telephone from Dubai. A government official in Baghdad confirmed their account. All spoke on condition of anonymity because of the sensitive nature of the information.

All three said the Iranians told al-Maliki's pilot that they were not informed in advance of the prime minister's need to cross Iran by air. None of the three had any information on whether that was true or an Iranian action designed to inconvenience and embarrass al-Maliki.

Iranian officials were unavailable to comment early Sunday.

If the refusal to allow Iraq's leader to cross Iran in his government plane was anything more than the result of confusion or poor communication, the incident would be a major snub for al-Maliki.

He is not known to have flown to Iran or used its airspace since he became prime minister in June. Iraqi President Jalal Talabani flew to Tehran in November for meetings with government officials.

Iraq has found itself in a very difficult diplomatic position since the U.S.-led invasion four years ago. It has at once found it necessary to court good relations with Tehran, its neighbor on the east, while not angering the Americans, who consider the Tehran regime to be what President Bush has called a member of the "Axis of Evil."

The United States has accused Iran of arming Iraqi militiamen and of trying to build a nuclear weapon.

The relationship became further complicated when the United States detained five Iranians in the northern city of Irbil in January and refused to release them or allow Iranian officials a chance to visit the men.

Iraq's position grew even more complicated last month when Iran captured a British navy crew and held it for 13 days. Britain, which has more than 7,000 troops in southern Iraq as part of the U.S.-led coalition in the country, patrols the Iraqi coastline in the Gulf, where territorial water boundaries are easily violated. Iran said the British crew was in its waters. Britain denied the charge.

Al-Maliki, a Shiite who owes his position to support from radical Shiite cleric Muqtada al-Sadr, would be expected to find favor with the Iranian regime, a Shiite theocracy. Tehran is said to be aiding al-Sadr's Mahdi Army militia with weapons and money in its fight to force an American troop withdrawal.

Al-Maliki, however, bowed to U.S. pressure early this year and demanded that al-Sadr rein in his militia in advance of the U.S.-Iraqi security crackdown in Baghdad. That operation is now in its eighth week and has seen several key Mahdi Army members detained by the U.S. military.

Al-Maliki has been unable to persuade the Americans to free a top Mahdi Army official, Qais al-Khazaali, who is believed to be Iran's main link to the militia. Al-Khazaali was captured by U.S. forces last month.

A U.S. Embassy official reached early Sunday said he was not aware of the Iranian refusal to allow al-Maliki to cross its airspace.

Al-Maliki was traveling to Japan to finalize a loan for Iraq to repair and upgrade the Iraq's energy industry. When it was announced in December, the loan was worth $707.53 million.