It was 10 years before the USSR and the USA at least tried to do something together in space (and Alexey Leonov took part in this as well!).
God only knows how great could be successes achieved if both superpowers turned the space exploration program into a joint demilitarized enterprise. But the history knows no "ifs"; so it was a USSR citizen and communist, colonel-lieutenant Leonov who did that step for mankind/
So, in fact, it was a part of the Soviet program of Lunar exploration, which was lost to the USA and never implemented. But this is another story.