"We are talking about the development of the system of reserve currencies and not about the replacement of the US dollar with other reserve currencies," President Dmitry Medvedev's top economic adviser Arkady Dvorkovich said.

"I think this talk (of replacing the dollar) is irrational," he said, speaking ahead of the Group of 20 summit in Pittsburgh next week.

"From our point of view, there should be several reserve currencies, including the dollar, the euro and several other currencies," Dvorkovich told a news conference.

His remarks came after calls by Russia to dump the dollar as the international currency of reference and diversify the global currency system.

Dvorkovich said that over the past months, including at the G20 summit in London in April, the Russian government have obtained a better understanding of the reforms of the global currency system it wanted to see.

"These discussions already can be more hands-on," he said.

He said a series of currencies, including the Chinese yuan, the British pound sterling, the Japanese yen and the Swiss franc had a good chance at gaining more prominence internationally.

Russia, along with China, has been a vocal proponent of diversifying the global currency system away from the dollar, which has dominated global finance since the end of World War II.

At the G8 summit in Italy in July, French President Nicolas Sarkozy joined the band in favour of jettisoning the dollar, insisting that "we cannot stick with just one single currency."