Russia has expressed surprise over Iran's military exercises near an Iranian nuclear power plant in the south of the country on April 6, Foreign Ministry spokesman Mikhail Kamynin said on Wednesday.

"Iran's air defense forces carried out firing practice near the nuclear power plant under construction in Bushehr, without notifying either the Russian embassy in Tehran or the construction project managers," Kamynin was quoted by the Interfax news agency as saying.

"In this context, the Russian embassy expressed its surprise and asked Tehran to inform the Russian personnel in Bushehr in advance about such plans," Kamynin said.

"Armed military exercises at 5 a.m. near the construction site of the Bushehr nuclear power plant, without any warning given to Russian experts, further raises tensions around the project," Sergei Novikov, spokesman of the Russian Agency for Nuclear Power,was quoted by the RIA Novosti news agency as saying.

The project, built under a 1995 contract, was suspended last month over what Russia called delayed payments from Iran since mid-January. On March 26, Moscow said Tehran had resumed financing,but added it still had to cover arrears. Negotiations are continuing this week in Tehran.

The project, implemented under UN supervision, was to be commissioned at the end of 2006, but the date has been repeatedly revised. Deputy head of the Iranian Atomic Energy Organization Mohammad Saeedi said on Tuesday that the plant will be commissioned by March 2008.

Iranian President Mahmoud Ahmadinejad said Monday the Islamic Republic had launched industrial production of nuclear fuel at the Natanz center, about 1,000 miles from the Israeli border. The UN Security Council tightened sanctions against Iran on March 24.