He said in a web-posted statement that the station will have to be de-orbited in a "planned crash so that there is no space junk left behind."
The colossal station is the biggest orbiting outpost ever built and can sometimes be seen from the Earth with the naked eye. It now consists of more than a dozen modules built by the U.S., Russia, Canada, Japan and the European Space Agency.
Russia sank its Mir space station in the Pacific in 1998 after five years in operation.
