MOSCOW - Russia has pushed back the launch of three moon missions, the Interfax news agency said on Tuesday, a setback to its ambitious lunar exploration programme as longtime space rival, the United States, celebrated an historic flight around the moon.

The launches of Russian spacecraft Luna-28, Luna-29, and Luna-30 have been postponed to 2032–2036, Interfax quoted Russian Academy of Sciences Vice President Sergei Chernyshev as saying.

It did not say when they had originally been slated to lift off, but the unexplained delays follow postponements last year to other Russian lunar and space missions and the crash of its unmanned Luna-25 craft into the surface of the moon in 2023.

Russia sees lunar exploration as vital to its national interests, the head of Russia's space agency Roskosmos said after the failed 2023 mission, saying the race was on to develop the moon's natural resources.

The Soviet Union launched the world's first satellite and sent the first human into space in the 1960s, but Russia's once mighty space programme has declined in the post-Soviet era, falling behind the U.S. and, increasingly, China.

This week, four astronauts from NASA's Artemis II mission were the first to fly around the moon in over 50 years, travelling further into space than any humans before them.

-Reporting by Reuters, Writing by Alessandra PrenticeEditing by Ros Russell/Reuters