Roskosmos said that specialists were analysing the situation but it has thus far given no further updates on Luna-25 since Saturday. Roskosmos did not answer repeated phone calls seeking comment on Sunday morning.

Unverified Russian-language Telegram channels reported that communication with the craft had been lost and Russia’s Moskovsky Komsomolets newspaper cited an unidentified specialist as saying that the craft may have been lost.

Failure for the prestige mission would underscore the decline of Russia’s space power since the glory days of Cold War competition when Moscow was the first to launch a satellite to orbit the Earth – Sputnik 1, in 1957 – and Soviet cosmonaut Yuri Gagarin became the first man to travel into space in 1961.

Russia has not attempted a moon mission since Luna-24 in 1976, when Leonid Brezhnev ruled the Kremlin. Luna-25 was supposed to execute a soft landing on the south pole of the moon on Aug. 21, according to Russian space officials.

Russia has been racing against India, whose Chandrayaan-3 spacecraft is also scheduled to land on the moon’s south pole this week, and more broadly against China and the United States which both have advanced lunar ambitions.

It was not immediately clear from official sources how serious the “abnormal situation” was – and whether or not Moscow could save the situation.

Under the headline “Space industry source: Luna-25 is lost”, the Moskovsky Komsomolets newspaper said that Alexander Ivanov, Roskosmos first deputy director, who directs orbital group projects, held an emergency meeting on the situation on Saturday evening.

Failure would underscore the pressure on Russia’s $2 trillion economy – and particularly its high-technology sectors – as it grapples with Western sanctions aimed at punishing Russia for the war in Ukraine.