The head of NASA, Bill Nelson, stressed that the timing of the implementation stages of the program will have to be shifted at least until 2025.

The U.S. authorities are still planning to land astronauts on the Moon in 2025, but do not rule out the possibility of postponing the mission to a later date.

“We will not send astronauts until it is safe. If this means a delay, then we will postpone [the flight]. However, we have every reason to believe that we are on schedule,” said NASA Chief Bill Nelson, speaking at a hearing in one of the committees of the U.S. Senate on Tuesday.

In the spring of 2019, NASA announced a three-stage project of the Artemis lunar program. At the third stage, the U.S. Space Agency expects to deliver astronauts to the moon, and then send them to Mars.

The timing of the implementation stages of the program was constantly changing due to various difficulties. Until recently, NASA insisted on continuing preparations for the landing of people on the Moon in 2024. At the end of last year, Nelson admitted that these plans are technically impossible. He stressed that the deadlines will have to be shifted at least until 2025.