Russia has mocked US President Donald Trump's "hysteria" about the first spaceflight of Nasa astronauts from US soil in nine years.
Moscow's space agency said it was puzzled by the excited response to the successful SpaceX flight, which fired two astronauts to the International Space Station over the weekend.
Officials at the agency, named Roscosmoc, also said on Sunday they were pleased there was now another way to travel into space.
SpaceX, the private rocket company of billionaire entrepreneur Elon Musk, launched two Americans into orbit on Saturday.
The landmark mission ended Russia's monopoly on flights to the International Space Station (ISS).
Trump, who observed the launch, said the United States had regained its place as the world's leader in space.
He added that US astronauts would soon land on Mars, and that Washington would have "the greatest weapons ever imagined in history."
NASA had had to rely on Roscosmos, Russia's space agency, to get to the ISS since its final space shuttle flight in 2011, and Trump hailed what he said was the end of being at the mercy of foreign nations.
The US success will potentially deprive Roscosmos, which has suffered corruption scandals and a number of malfunctions, of the lucrative fees it charged to take US astronauts to the ISS.
"The hysteria raised after the successful launch of the Crew Dragon spacecraft is hard to understand," Vladimir Ustimenko, spokesman for Roscosmos, wrote on Twitter after citing Trump's statement.
"What has happened should have happened long ago. Now it's not only the Russians flying to the ISS, but also the Americans. Well that's wonderful!"
What is SpaceX?
Here's what you need to know...
SpaceX is a cash-flushed rocket company that wants to take man to Mars.
It was set up by eccentric billionaire Elon Musk in 2002 and is based in Hawthorne, California.
SpaceX's first aim was to build rockets that could autonomously land back on Earth and be re-used.
Musk hoped the technology would make flying and operating space flights far cheaper.
SpaceX currently uses its reusable rockets to fly cargo to the International Space Station for Nasa.
It also carries satellites and other space tech into orbit for various international governments and companies.
The company will take astronauts up to the ISS for the first time in 2020.
Other future missions involve carrying tourists and astronauts to the Moon.
Musk has repeatedly said he believes humanity must colonise Mars to save itself from extinction.
He plans to get a SpaceX rocket to the Red Planet sometime in the 2030s.
SpaceX's capsule docked with the ISS on Sunday.
Roscosmos head Dmitry Rogozin congratulated NASA chief Jim Bridenstine for the success.
"Bravo! I know how anxious you were for this major event to become a success," Rogozin wrote on Twitter.
Rogozin said he had appreciated a barbed joke by Musk referencing his own 2014 barb that the United States should try using a trampoline to get to the ISS.
Musk told a post-launch news conference "the trampoline is working".
Ustimenko said Russia planned to test two new rockets this year and to resume its lunar programme next year.
"It will be interesting," said Ustimenko.
Most read in Science
In other news, take a look at The Sun's recap of Saturday's SpaceX launch here.
READ MORE SUN STORIES
The crew docked with the ISS on Sunday where they will carry out various space experiments.
And, could you fly Elon Musk’s SpaceX ship? Try this free simulator to find out.
We pay for your stories! Do you have a story for The Sun Online Tech & Science team? Email us at [email protected]