For the first time in 20 years, a Russian cosmonaut rocketed from the US today, launching to the International Space Station alongside Nasa and Japanese astronauts despite tensions over the war in Ukraine.

"We're so glad to do it together," said Anna Kikina, Russia's lone female cosmonaut, offering thanks in both English and Russian. "Spasibo!"

She was among the three newcomers on the flight, alongside Marine Colonel Nicole Mann, the first Native American woman to orbit the world, and Navy Captain Josh Cassada. They were joined by Japan Space Agency's Koichi Wakata, who is making his fifth spaceflight.

"Awesome!" radioed Mann. "That was a smooth ride uphill. You've got three rookies who are pretty happy to be floating in space right now."

They're due to arrive at the space station tomorrow, 29 hours after a noon departure from Nasa's Kennedy Space Centre, and won't be back on Earth until March. They're replacing a US-Italian crew that arrived in April.

Their SpaceX flight was delayed by Hurricane Ian, which devastated parts of the state last week.

"I hope with this launch we will brighten up the skies over Florida a little bit for everyone," Wakata said before the flight.

Kikina is the Russian Space Agency's exchange for Nasa's Frank Rubio, who launched to the space station two weeks ago from Kazakhstan aboard a Soyuz rocket. He flew up with two cosmonauts.

The space agencies agreed over the summer to swap seats on their flights in order to ensure a continuous US and Russian presence aboard the 420km-high outpost. The barter was authorised even as global hostilities mounted over Russia's invasion of Ukraine in late February. The next crew exchange is in the spring.

Shortly before liftoff, Nasa Administrator Bill Nelson said the key reason for the seat exchange is safety — in case an emergency forces one capsule's crew home, there would still be an American and Russian on board.

In the meantime, Russia remains committed to the space station through at least 2024, Russia space official Sergei Krikalev assured reporters this week. Russia wants to build its own station in orbit later this decade, "but we know that it's not going to happen very quick and so probably we will keep flying" with Nasa until then, he said.

A SpaceX Falcon 9 rocket with astronauts lifts off from Kennedy Space Centre in Cape Canaveral, Florida today for a mission to the International Space Station. Photo / AP

Beginning with Krikalev in 1994, Nasa started flying cosmonauts on its space shuttles, first to Russia's Mir space station and then to the fledgling space station. The 2003 Columbia reentry disaster put an end to it. But US astronauts continued to hitch rides on Russian rockets for tens of millions of dollars per seat.

Kakina is only the fifth Russian woman to rocket off the planet. She said she was surprised to be selected for the seat swap after encountering "many tests and obstacles" during her decade of training. "But I did it. I'm lucky maybe. I'm strong," she said.

Mann, a member of the Wailacki of the Round Valley Indian Tribes in California, took along her mother's dream catcher, a small traditional webbed hoop believed to offer protection. Retired Nasa astronaut John Herrington, of the Chickasaw Nation, became the first Native American in space in 2002.

"I am very proud to represent Native Americans and my heritage," Mann said before the flight, adding that everyone on her crew has a unique background. "It's important to celebrate our diversity and also realise how important it is when we collaborate and unite, the incredible accomplishments that we can have."

As for the war in Ukraine, Mann said all four have put politics and personal beliefs aside, "and it's really cool how the common mission of the space station just instantly unites us."

Added Cassada: "We have an opportunity to be an example for society on how to work together and live together and explore together."

Elon Musk's SpaceX has now launched eight crews since 2020: six for Nasa and two private groups. Boeing, Nasa's other contracted taxi service, plans to make its first astronaut flight early next year, after delays to fix software and other issues that cropped up on test flights. - AP