A view of the reactor at the nuclear power plant in Bushehr, 1200 km south of Tehran.

Russians often express their displeasure with a country in a peculiar way. When the problem with Georgia flared in 2008 over the separatist republic of South Ossetia, Russian authorities suddenly discovered a serious problem with Georgian cognac and mineral water. Now, as Russia-Belarus tension grows, problems have been found with milk from Belarus.

The Kremlin can also express its mood in other ways beyond food and drink, as it is doing with the Bushehr nuclear plant it has been building in Iran since 1995. Russia is well aware of the importance of the plant, both for Iran, which needs the nuclear energy, and the United States, which views it as another step in the direction of Tehran's alleged nuclear weapons program.

Construction of the plant - two 1,300-megawatt pressurized water reactors - started in 1975 by Germany's KWU. The completion date was planned for 1982, but in 1979 work was suspended following the Iranian revolution.

In 1995, Russian state-run company Atomstroiexport began building the first reactor, with startup scheduled for this year. In March, the head of Russia's state nuclear power corporation Rosatom, Sergei Kiriyenko, announced that Russia had completed construction. Pre-launch tests were then conducted and it is expected to be up to full capacity by the end of March 2010. The International Atomic Energy Agency, or IAEA, of which Iran is a member state, will oversee operation of the plant.

Last month, though, Russian state-run RIA-Novosti quoted the head of Atomstroiexport, Dan Belenky, as saying the company was trying to alter the financing of the plant, for which Iran is paying Russia more than US$1 billion, and that the initial start-up would be delayed from August to an unspecified date.

Belenky said that some Russian banks - which were not named - were refusing to work with Iran and this had complicated financing. Belenky stressed the problem was not on the Iranian side but with the Russian banks - as if Russian banks are absolutely independent entities and that Moscow could not compel them to work with Iran.

Belenky also recalled an objection raised a few years ago by Prime Minister Vladimir Putin - then president - during a trip to Iran that Bushehr had a lot of non-Russian equipment and that this created an additional problem.

In similar vein, Russia recently rejected providing Iran with the S-300 long-range surface-to-air anti-missile defense system that could potentially protect it in the event of an American or Israeli attack. The Russian official seems to have accepted the proposition of Israeli Foreign Minister Avigdor Lieberman, during a visit to Moscow, that Russia and Israel should coordinate their sales of weapons so as not to endanger mutual interests.

Reading into these signals, it appears the idea of a Russian-Iranian axis, popular in certain circles at the end of Boris Yeltsin's time in the late 1990s to the beginning of the Putin era, is passe. It shows that the relationship with Iran is pragmatic, opportunistic - and fleeting.

It also implies that Russia is pleased by the indications of US Secretary of Defense Robert Gates that America might delay implementing an anti-missile shield in Eastern Europe and that there is no viable US support of Ukraine in its confrontation with Russia over gas supplies.

Moscow has repeatedly insisted that the installation of US missiles in countries close to its borders would change the strategic balance in Europe and that such a deployment would be interpreted as a military threat.

The International Energy Agency warned this week that the flow of Russian gas through Ukraine may be disrupted at any time. Gazprom, the giant Russian utility, and Naftogaz, its Ukrainian counterpart, are at odds over unpaid Ukrainian gas bills. About 80% of Gazprom's gas shipments to Europe flow through Ukrainian pipelines. This is a quarter of the continent's demand for gas. Russian President Dmitry Medvedev said that Ukraine could be required to pay in advance for its gas so as to prevent any further delays in payment.

In the bigger picture, Russia appears to be softening towards the US while adopting a more reserved approach to Iran. Moscow has watched the US's troubles in the Middle East and its overall geopolitical decline with some concern.

Continued instability in the Caucasus is viewed by the Russian elite as directly relating to Muslim global terrorism, as Medvedev made clear in recent comments. The Russian elite understands that the US's global departure could well expose Russia to the not very friendly, or, at least, unpredictable, Muslim world.

In this situation, Moscow would rather cooperate with the US than with Iran, which, in the long run, might create even more problems than the US. This could have a direct impact on the international pressure on Iran over its uranium-enrichment program, which many believe is not for peaceful purposes. This could result in more sanctions on Tehran in addition to the two rounds imposed by the United Nations and the unilateral ones slapped on by the US.

Moscow, by pointing to "problems" with Bushehr, is sending a message not so much to Teheran as to Washington. Still, Russia will not abandon Iran unless it receives appropriate geopolitical concessions, such as a free reign for Russia in the former Soviet Union space. This is a heavy price and will definitely give Washington something to think about.

For this reason, Moscow's flirtation with the US could be as opportunistic and unstable as its flirtation with Tehran.

Dmitry Shlapentokh, PhD, is associate professor of history, College of Liberal Arts and Sciences, Indiana University South Bend. He is author of East Against West: The First Encounter - The Life of Themistocles, 2005.