MOSCOW (Reuters) - Russia has signed into law United Nations economic sanctions that world powers agreed to in March, according to a presidential decree published by the Kremlin on Thursday.

The United Nations Security Council imposed a third round of sanctions on Iran on March 3 for refusing to suspend sensitive nuclear activities.

The Russian decree, signed by Vladimir Putin before he left office, calls for restrictions on travel and financial transactions with certain Iranian individuals and companies.

The United States and other Western nations suspect Iran of using its civil nuclear program as a cover to develop nuclear weapons. Iran says its nuclear program is needed to generate electricity so that it can export more of its oil and gas.

Russia has been building Iran's first nuclear power station at Bushehr on the Gulf coast, in southwest Iran. Iranian officials say it may start up later this year.

(Reporting by Guy Faulconbridge, editing by Christian Lowe and Ralph Boulton)

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