This long exposure photo shows the flight path of the Soyuz TMA-12M rocket as it launched from Kazakhstan. Photo: Bill Ingalls/Nasa

Two Russian cosmonauts and a US astronaut blasted off for a six-month stay aboard the International Space Station on Tuesday, a partnership unaffected by the political rancour and economic sanctions triggered by Russia’s annexation of Crimea.

The Russian Soyuz rocket carrying cosmonauts Alexander Skvort­sov and Oleg Artemyev and Nasa astronaut Steven Swanson lifted off at 5.17pm EDT/2117 GMT from the Baikonur Cosmodrome in Kazakhstan.

The trip to the space station, a $100 billion research laboratory that flies about 418km above earth, was scheduled to take about six hours.

However, an engine burn caused the crew’s Soyuz capsule to skip two planned steering manoeuvres, delaying the crew’s arrival until today.

“The crew is in no danger. The Soyuz (is) equipped with plenty of consumables to go even beyond the next two days, should that be become necessary. Nobody expects that that will be the case,” mission commentator Rob Navias said during a Nasa Television broadcast.

The Soyuz TMA-12M spacecraft carrying the International Space Station crew of US astronaut Steven Swanson, with Russian cosmonauts Alexander Skvortsov and Oleg Artemyev blasting off from its launch pad at the Baikonur cosmodrome. Photo: Maxim Shemetov/Reuters

Russia’s state television channel Rossiya-24 quoted national space agency Roscosmos as saying the flight of the Soyuz spaceship was now taking place “in a reserve mode” after its orientation engines failed to ignite.

“It’s all normal on board,” it said.

Docking was tentatively retargeted for 2358 GMT today.

Several hours before the docking, Soyuz will make a final emergency manoeuvre to enter the orbit of the space station, RIA news agency quoted a Russian space official as saying.

The arrival of Skvortsov, Artemyev and Swanson will return the station to a full six-member crew.

The orbital outpost, a project of 15 nations, has been short-staffed since two other cosmonauts and a Nasa astronaut returned to earth on March 11.

The space station partnership, overseen by the US and Russia, so far has been immunised from the political and economic fallout following Russia’s invasion of Ukraine’s Crimean peninsula.

I mean, we’re three really good friends climbing into a Soyuz [capsule] to fly into space. All politics aside, there’s no doubt it’s going to work for us

“We don’t want to see political turmoil and it could ultimately get in the way of our spaceflight, but from the operator standpoint... this is absolutely a non-issue for us,” Nasa astronaut Reid Wiseman, who is due to fly to the station in May, said in a CBS News interview on March 18.

“I mean, we’re three really good friends climbing into a Soyuz [capsule] to fly into space. All politics aside, there’s no doubt it’s going to work for us,” Wiseman said.

The US currently pays Russia more than $63 million per seat to fly its astronauts to and from the space station.