US astronaut Michael Fincke and Russian cosmonaut Gennady Padalka were originally due to perform their first space walk on June 16.

But the sortie was delayed to avoid "communication problems on that day because of the planned June 16 launch of a satellite from Baikonur," Russia's launch site in the former Soviet republic of Kazakhstan, Sergei Puzanov, a NASA representative in Russia, had told AFP.

Fincke and Padalka began a six-month mission on the ISS on April 21.

SPACE.WIRE