Russia and Venezuela signed on Friday an agreement on the construction of a nuclear power station in the South American country as part of Venezuelan President Hugo Chavez's visit to Moscow.

The agreement was reached in April 2010 during Russian Prime Minister Vladimir Putin's visit to Caracas.

When asked during a daily press briefing in Washington if the United States had any concerns regarding the deal - considering that Venezuela had "a little bit of ties with Iran" - Philip Crowley said "well, this is something that we will watch very closely."

"It is certainly a right of any country to pursue civilian nuclear energy, but with that right come responsibilities and we would expect Venezuela, Russia, or any other country pursuing this kind of technology to meet all international obligations," Crowley said, adding "the last thing we need to do is see technology migrate to countries or groups that should not have that technology."

"But we have confidence in Russia," he said.

Western powers fear that Iran, which is already under four sets of UN sanctions over its controversial nuclear program, may obtain advanced nuclear technologies, which would jeopardize security in the Middle East.

At Friday's signing ceremony in Moscow, President Dmitry Medvedev said cooperation with Venezuela in nuclear field does not constitute a threat for other countries.