The European Space Agency has ended cooperation with Russia on a number of missions that could unearth extraterrestrial life. It will discontinue activities on three trips to the Moon - Luna-25, 26 and 27.
Space chiefs have also suspended collaboration on the alien-hunting ExoMars operation, which planned to land a rover on Mars to drill into the soil and search for signs of extraterrestrial life.
A spokesman for the agency said: "As with ExoMars, the Russian aggression against Ukraine and the resulting sanctions put in place represent a fundamental change of circumstances and make it impossible for ESA to implement the planned lunar cooperation.
"As an inter-governmental organisation mandated to develop and implement space programmes in full respect with European values we deeply deplore the human casualties and tragic consequences of the aggression towards Ukraine.
"While recognising the impact on scientific exploration of space ESA is fully aligned with the sanctions imposed on Russia by its member states."