An unusual "Tweet-up" -- a meeting of people who know each other onTwitter -- involving an ambassador, an astronaut and a prime minister has takenplace on a video-link between Japan and the International Space Station.Prime Minister Shinzo Abe and US ambassador to Japan Caroline Kennedy chattedwith the Japanese commander of the ISS, Koichi Wakata, as he circled the Earthhundreds of miles up.The three, who are all active on the micro-blogging site, talked on Thursday eveningabout daily life aboard the station, while Kennedy and Wakata traded complimentson their activities in the blogosphere."It's an honour to be able to speak with you," Kennedy, the only surviving daughterof assassinated US president John F. Kennedy said."Congratulations Commander Wakata on being the first Japanese commander of thespace station and I am glad that we follow each other on Twitter," Kennedy said."Ambassador Kennedy, it's quite an honour that you follow my tweets," Wakatareplied.Wakata who was flanked by fellow space-farers from Russia and the US, battled withzero-gravity to grab the microphone and make himself heard back on Earth as Abeaddressed him."You are the first Asian to become commander of the ISS," the Japanese PM said."Are there days when you think that it is hard work?"Wakata, a practised diplomat as well as an astronaut said the multi-national crewwas an effective unit."I think we really work well as a team," he said. "But we are more than just crewmates, qualities from all the countries we represent complete each other and we cancommunicate perfectly," he added.The conversation took place hours after a a Russian cargo ship docked with the ISS,bringing the crew crucial supplies and water.Earlier this month NASA announced that it was cutting space cooperation withRussia -- except over the ISS -- because of Moscow's actions in Ukraine, including the takeover of Crimea last month.NASA has been wholly reliant on Russia for delivering astronauts to the space station since the US retired its space shuttles in 2011.