The European Space Agency said on Monday it was studying the impact of US budget proposals that include cuts to NASA moon programmes in which it has a role, and said it remained open to cooperation with the US space agency.

Ministers from ESA’s governing council will discuss “potential actions and alternative scenarios” at a meeting in June, the 22-nation European agency said in a statement.

US budget outlines released on Friday called for phasing out NASA’s Space Launch System (SLS) rocket and its Orion crew vehicle, which includes a key service module supplied by Europe’s Airbus on behalf of ESA.

The White House has called SLS and Orion “grossly expensive” and says they have far exceeded their budgets.

The budget summary also called for halting the planned Gateway lunar-orbit platform, which would play a key part in future Artemis moon missions and includes elements to be built by Franco-Italian Thales Alenia Space.

ESA said the US budget proposals were a “work in progress,” but it has begun discussing the implications with NASA.

“ESA remains open to cooperation with NASA on the programmes earmarked for a reduction or termination, but is nevertheless assessing the impact with our member states in preparation for ESA’s June Council,” the statement said.

In that meeting, on June 11-12, ESA and its member states will assess “potential actions and alternative scenarios” for the relevant ESA programmes and European industry, it added, without elaborating on other possible options.

The Artemis program, launched during President Donald Trump’s first administration, aims to return humans to the moon and use the exercise as a testbed for later Mars missions. It involves dozens of private companies and countries, including European countries.

The cuts would affect Orion’s European Space Module, which manoeuvres the spacecraft and supplies water and oxygen. According to manufacturer Airbus, it is the first time NASA has granted a non-US firm such a critical role in human spaceflight.

European contributions to Gateway include an inhabited module known as Lunar I-Hab built by Thales Alenia Space, the Lunar View observation and logistics module led by the same company, and a communications set-up called Lunar Link.

The US and ESA signed a Gateway agreement in 2020 outlining Europe’s contributions to the project, modeled largely on the US agreement with Europe on the International Space Station.

Airbus and Thales did not immediately respond to requests for comment.