WASHINGTON, April 28. /TASS/. The United States and Russia are cooperating in the sphere of space despite disagreements over the conflict in Ukraine, US National Aeronautics and Space Administration (NASA) chief Bill Nelson has said.

"One of the great ironies is that we can be at such odds with the Russian government and President Putin over the inexcusable things that are going on in Ukraine and have a cooperative space program with the Russians just like we've had since 1975," he said during hearings at the US House of Representatives’ Science, Space, and Technology Committee.

In his words, his country has been maintaining "cooperation in the civilian space program with the Russians" since the Cold War period.

"We then built the International Space Station <…> We built it together and we have to operate it together. And that goes on today without a hitch and that's the irony I'm talking about," he said.

In Nelson’s words, relations with China in this area have been totally different.

"They have not cooperated at all. They have their own space station. That's part of the progress they've made in the last 10 years. And they are good, but they are very secretive and non transparent," the NASA chief said.

Nelson told the Senate Appropriations Committee of the US Congress on April 19 that the US and its partners were maintaining "professional, competent relationship" with Russia with regard to space. This is reflected in joint work of US astronauts and Russian cosmonauts aboard the International Space Station (ISS) and in the Russian-US seat swap agreement. The deputy chairman of Russia’s Security Council, Dmitry Medvedev, believes it is a net positive that Russia and the United States continue to cooperate in crewed space flights.