Space tourists will be again able to fly on Russian Soyuz spacecraft to the International Space Station in two to three years, Russia's top space official said Friday.

Russia stopped sending tourists to space last year because the International Space Station (ISS) crew has increased from three to six, and all the places on board the spacecraft have been reserved for Russian and foreign astronauts.

'Our capabilities to produce and launch spacecraft have doubled (since 2009), so the possibility (of space tourist flights) could arise again after 2012-2013,' said Anatoly Perminov, the head of the Russian Federal Space Agency Roscosmos.

Russia's RSC Energia corporation recently said it had the capacity to build five Soyuz spacecraft per year instead of four, meaning that at least one Soyuz spacecraft could be used for space tourism purposes in the future.

Space tourists started flying to the ISS in 2001.

Dennis Tito, an American businessman and former NASA scientist, became the first space tourist when he visited the ISS in 2001. He was followed by South African computer millionaire Mark Shuttleworth in 2002, and Gregory Olsen, a US entrepreneur and scientist, in 2005.

In 2006, Anousheh Ansari, a US citizen of Iranian descent, became the first female space tourist.

US games developer Richard Garriott, the son of former NASA astronaut Owen K. Garriott, went into orbit for 11 days in October 2008 on board a Russian Soyuz TMA-13.

US space tourist Charles Simonyi, one of the founders of Microsoft, made two trips to the ISS - in 2005 and 2009.

Guy Laliberte, the Canadian founder of entertainment company Cirque du Soleil, traveLled to the ISS in October last year.