Russia does not foresee blasting any more “space tourists” into orbit in Dennis Tito’s wake until it reaches agreement with the United States about amateur astronauts, the head of the Russian space agency said Friday.

“We must work out between now and July the rules for selecting, training and sending non-professional cosmonauts into space in order to avoid any conflict,” Yuri Koptev told a news conference here.

NASA objected to the pioneering space mission last week by 60-year-old American businessman Dennis Tito, who paid Russia 20 million dollars for an eight-day trip to the International Space Station.

“There are other volunteers” for space travel, Koptev told journalists Friday without giving any details.

The latest comments followed earlier comments from Russian space authorities on Tuesday dismissing reports that they had a successor to US businessman Dennis Tito lined up for a tourist jaunt in space, saying no further places were available for at least two years.

Rumours that the Russian Space Agency, Rosaviacosmos, was about to announce a second space visitor among the numerous millionaires said to have expressed an interest are unfounded, RSA spokesman Sergei Gorbunov told the RIA Novosti news agency late Monday.

Western media reports had suggested, after Tito’s successful lift-off into orbit on April 28, that at least two people, notably “Titanic” movie director James Cameron, were negotiating with Russian officials for a 20-million-dollar (22-million-euro) trip to the International Space Station.

But Gorbunov said all places aboard upcoming scheduled Russian flights to the ISS were reserved for professional cosmonauts.

It was possible no further places would be available for another five years, he said.

“We insisted on Dennis Tito’s flight going ahead because there was a spare place aboard the ship leaving for the ISS,” he noted, adding that the third seat aboard the Soyuz shuttle on the next few flights were already taken up.

Tito, a former engineer with the US space agency NASA, completed his eight-day flight, which included six days aboard the ISS, on Sunday.

NASA expressed grave misgivings about his flight, fearing that his lack of professional training could impede work aboard the still uncompleted space station.