A Russian and an American returned to Earth on Wednesday with their Japanese commander aboard a Soyuz capsule in the first such landing since Moscow's ties with the West imploded over Ukraine. Koichi Wakata -- the first Japanese leader of an International Space Station mission -- NASA's Rick Mastracchio and Russian cosmonaut Mikhail Tyurin completed a 188-day stay that began months before Europe was thrown into its worst security crisis since the Cold War. Ex-Soviet Ukraine has since seen a part of its territory seized by Kremlin forces and the West retaliate with sanctions that have prompted Russia -- provider of the sole manned link to the orbiting laboratory -- to question the wisdom of future cooperation in space. A top Russian minister stepped up the rhetoric on Tuesday by warning that Moscow may reject Washington's request to extend the station's lifespan by four years until 2024. The trio was all smiles on Wednesday as they clambered out of the conic capsule in their bulky space suits after splashing down without mishap in the sand-swept steppe of Kazakhstan. But Tyurin hinted of the overriding tensions by singing the praises of Russian space equipment that may one day slip out of Western hands. "The landing was outstanding," Tyurin said in comments broadcast on Russian state television. "It was simply ideal. We do have some wonderful technology!" Moscow is fiercely proud of its rockets and still fetes its ability to beat the United States during the Soviet-era space race by putting the first man in orbit in 1961. And a top minister in charge of the military-industrial complex warned that Moscow may strike back at new high-technology export restrictions that Washington imposed in retaliation at the Kremlin's Ukrainian land grab by limiting US access to Russian space equipment. Deputy Prime Minister Dmitry Rogozin said that Russia was "planning to only need the ISS until 2020" and then spend funding "on other promising space projects." - US 'hopeful' about cooperation - NASA had said in January it would like the orbiter's lifespan extended in order to improve its marketability and chances of getting commercial investment in space. Rogozin added that Moscow could also prohibit the United States from using a Russian engine that the Pentagon employs in Atlas V rocket launches from shooting up military satellites. NASA responded to Rogozin's warning with caution. "We have not received any official notification from the government of Russia on any changes in our space cooperation at this point," the US government agency said in a statement. US State Department spokeswoman Jen Psaki added that "we’ve had a long cooperation on our space programme with the Russians and we’re hopeful that will continue." But Psaki also appeared to suggest that the United States might not be as reliant on Russia's space technology as some in Moscow might like to think. "We do have a number of materials of the same kind that we can use in the future," she said. NASA hopes to keep the ISS spinning 400 kilometres (250 miles) above Earth a bit longer to help private US firms such as SpaceX upgrade rockets it now uses to ferry up cargo to also be able to accomodate astronauts. The United States has relied on the Soyuz for all manned missions since retiring its Shuttle Programme in 2011. The current ISS team is comprised of NASA astronaut Steve Swanson and Russian crewmates Alexander Skvortsov and Oleg Artemyev.