A US move to freeze the Lunar Gateway orbiting space station could render Japan’s new technologies redundant – but its space agency is expected to be diplomatic in its response.

The gateway project was initially planned as an installation that would orbit the moon as part of the United States’ Artemis programme, which recently made headlines for a record-breaking journey that went deeper into space than anyone had ever flown before.

Artemis’ aim is to return astronauts to the moon’s surface for the first time since 1972, with the space station a key element of the project.

Questions were raised about the project in May last year, when the Office of Management and Budget (OMB) expressed concern over escalating costs, commercial alternatives and shifting priorities.

Nevertheless, US$2.6 billion of funding over two years was earmarked for the project last July under President Donald Trump’s One Big Beautiful Bill Act.

On March 24, however, Nasa announced it was freezing the project to focus on the construction of a base on the surface of the moon, with future manned missions to Mars in mind.

The Japanese government was reportedly taken by surprise by the decision.

Since 2017, the Japan Aerospace Exploration Agency (JAXA) had been working on the habitation facilities aboard the space station, which also involved inputs from the space agencies of Europe, Canada and the United Arab Emirates.

Japanese space engineers had also been developing the HTV-X uncrewed resupply vehicle. It was first launched in October 2025 to resupply the International Space Station, which is expected to be decommissioned in 2031.

JAXA has invested at least 12.5 billion yen (US$78.5 million) in the two components of the space station over the last three years.

‘Not fans of space’

It is now expected to focus all its attention on the third element of its collaboration with Nasa, the pressurised lunar rover that is being developed with Toyota to allow astronauts to drive on the moon.

“We are aware of the announcement made by the Nasa administrator regarding the temporary suspension and review of the Gateway programme,” JAXA said in a statement.

“Our contribution to a lunar base … has already been agreed, under the Implementation Arrangement between the Japanese government and Nasa for lunar exploration using a crewed pressurised rover, that Japan will develop and provide.”

The agency will continue to work “diligently” on the vehicle, it said.

Nasa has promised two opportunities for Japanese astronauts to land on the moon as part of future Artemis missions.

“Regarding development activities for future lunar missions, we will work in close coordination with our international partners to ensure that these efforts contribute to Japan’s overall human space exploration activities,” the statement said.

Kazuto Suzuki, a science and technology professor at the University of Tokyo and a member of the Japanese government’s committee on National Space Policy, said the Lunar Gateway had not been completely axed as Congress would need to make a final decision, but the new focus on a base on the surface of the moon made Nasa’s priorities clear.

“The OMB is being very tight with spending under this US government and these are not Apollo mission-type people,” he said. “They are not really fans of space and just see this as a huge waste of money.”

A manned base on the moon is seen as a better use of funds, according to Suzuki, even though that leaves Japan only able to contribute the rover.

A Japanese academic who declined to be named as he serves as an adviser to government agencies, said the decision and the failure to tell Tokyo in advance underlined how the US had become an unreliable partner.

“It’s a trend with the US taking unilateral decisions without consulting potential and real partners on major projects and issues,” he said. “We are seeing this in many areas, from the political arena to security, technology, trade and others.”

However, JAXA has limited opportunities to develop and deploy new technologies in space exploration because Nasa is so dominant in the sector.

“There are not many alternatives, but I think JAXA and the Japanese government are going to be more careful of how they partner with Nasa the next time,” he said.