Sam Francisco, Jul 31 (IANS): The US Government Accountability Office (GAO) has squashed Jeff Bezos-run Blue Origin's challenge to space agency NASA for picking Elon Musk-owned SpaceX for its prestigious $2.9 billion Moon lander programme.

Blue Origin and defence contractor Dynetics had filed a protest with the US GAO against NASA for awarding $2.9 billion contract to SpaceX for landing astronauts on the Moon by 2024.

The US space agency was expected to pick two lunar lander prototypes (including one of Blue Origin's) but funding cut from US Congress led the agency to select SpaceX over Blue Origin.

GAO on Friday rejected Blue Origin's protest, saying "there was no requirement for NASA to engage in discussions, amend, or cancel the announcement as a result of the amount of funding available for the programme," reports The Verge.

In a tweet, Musk responded to the news by tweeting "GAO" with a flexing bicep emoji.

Fresh from his trip to the edge of space, Amazon Founder Jeff Bezos earlier this week even offered NASA a discount of up to $2 billion to give his space company Blue Origin the human lunar landing system (HLS) contract.

Escalating his space war with Musk, Bezos in an open letter to the NASA Administrator Bill Nelson said that his company would close US space agency's near-term budgetary shortfall and producing a safe and sustainable lander that will return Americans to the surface of the Moon - this time to stay.

"We stand firm in our belief that there were fundamental issues with NASA's decision, but the GAO wasn't able to address them due to their limited jurisdiction," a Blue Origin spokesperson said in a statement.

NASA said the GAO ruling allows the agency and SpaceX to come up with a timeline for landing humans on the Moon.

The moon lander contract is part of NASA's Artemis programme, which aims to return astronauts to the moon by 2024 as a stepping stone to the first human mission to Mars.