Russian Space Agency Roscosmos went back on its words on Thursday after an uproar over a statement by agency’s deputy head, who said on Wednesday that Russia and its partners plan to sink the International Space Station (ISS) in the ocean after its scheduled retirement in 2020.

"After it completes its existence, we will be forced to sink the ISS,” said deputy head of Roskosmos space agency Vitaly Davydov.

Roscosmos backtracked amid ongoing criticism over Davydov’s comments.

"The partners have agreed to continue the ISS operation until 2020. The partners will also approve an extended period of the ISS," Roscosmos press secretary Anna Vedishcheva was quoted as saying by Russian news agency Interfax-AVN.

The ISS was placed in Earth’s lower orbit in 1998 and is a joint project of space agencies from the United States, Russia, Europe, Japan and Canada.

“It cannot be left in orbit, it's too complex, too heavy an object, it can leave behind lots of rubbish," Davydov said.

Mir space station was also sunk by Russia into the Pacific Ocean in 2001 when its 15-year life cycle ended.

The International Space Station is pictured against the Earth in this image taken from NASA TV May 23, 2010. REUTERS/NASA TV