In the latest blow to relations, Iran's foreign ministry said Sunday it was summoning Iraq's top diplomat here over claims that four Iranian spies have been arrested in Baghdad.

"Today we are going to summon the Iraqi charge d'affaires to the Iranian foreign ministry, and we are going to ask him to give us proof," spokesman Hamid Reza Asefi told reporters.

"He should tell us whom they have arrested and if they have proof to give us," he added, saying Iraqi officials should also "stop creating a bad atmosphere" between Iran and Iraq.

On Saturday a spokesman for the Iraqi interior ministry said four Iranian intelligence officers had been arrested by Iraqi authorities on suspicion of spying and carrying out acts of sabotage in the country.

Asefi also snubbed a call from Iraq's interim Defence Minister Hazem al-Shaalan, who has been widely lambasted in the Iranian press, that Tehran immediately return Iraqi planes sent to Iran before or during the 1991 Gulf War.

"We will discuss these (issues) with the coming elected government officials, and not with the interim government," Asefi said in what amounted to a major snub.

Iran has yet to formally recognise the Iraqi interim government, which has been described by Iranian supreme leader Ayatollah Ali Khamenei as "lackeys" of the Americans.

Shaalan said in an interview with the Kuwaiti daily newspaper Al-Anbaa that Iran should send back 130 planes "now".

Tehran has insisted that it was holding only 22 Iraqi planes which Saddam Hussein's regime sent to Iran to avoid attacks by US-led forces liberating Kuwait and that it was ready to return them if asked by the United Nations.

Tensions between Iraq and Iran have mounted in recent weeks, after Shaalan told The Washington Post he had seen "clear interference in Iraqi issues by Iran" and accused Tehran of taking over some Iraqi border posts and sending spies and saboteurs into Iraq.