The eagerly-awaited manned travel for conducting scientific research in space will take at least another 15-20 years, Russian cosmonaut Mikhail Kornienko said here on Thursday.
He said there was a huge scope for higher participation in space programmes by the private sector players both from Indian and Russia.
Lauding Indian and Chinese space programmes for "making great progress", Kornienko urged the need for similar joint efforts by countries like Russia, India and China for the success of space exploration.
Speaking of his long experiences in space, he referred to the problem of debris in space as "very serious" and even the International Space Station Mission had suffered from it.
Kornienko, who spent almost a year on the ISS mission from March 2015, among the longest in the world, was addressing a gathering on his space travels at the Nehru Science Centre as part of the two-day Rosatom Festival of Science and Culture which opened here on Thursday.
Emphasising the involvement of the media and entertainment sectors of both countries in the efforts to popularize space science, he stressed this could be achieved by moving away from sensationalism and 'breaking news'.
The cosmonaut, along with NASA Astronaut Scott Kelly, spent a staggering 342 days in space on the International Space Station (ISS) in 2015.
Kornienko, 58, an engineer, and Kelly were together on the 'one-year crew mission' which started on March 27, 2015, the longest by any spacemen aboard the ISS.
Among other things, they studied the effects of prolonged period in space on human, the physical, psychological and emotional aspects that would help future manned explorations planned in the solar system.
Selected for Cosmonaut training in 1998, Kornienko has spent a total of a little more than 516 days in space and also carried out two space walks lasting over 12 hours total in his extra-terrestrial career.
Rosatom State Nuclear Energy Corp of Russia, which boasts of the largest portfolio of nuclear power plant construction projects in the world, is implementing the Kudankulam Nuclear Power Plant in Tamil Nadu jointly with Nuclear Power Corp of India Ltd, "which is a symbol of Indo-Russian relations", said its Vice-President (India) Andrie Lebedev.
The company also has the world's largest uranium reserves, ranking fourth in uranium production to cover 17 percent of the global nuclear fuel market.