CAPE CANAVERAL, Fla. – NASA is paying $424 million more to Russia to get U.S. astronauts into space, and the agency’s leader is blaming Congress for the extra expense.

NASA announced its latest contract with the Russian Space Agency on Tuesday. The $424 million represents flights to and from the International Space Station aboard Russian Soyuz spacecraft, as well as training, for six astronauts in 2016 and the first half of 2017.

That’s $70.6 million per seat — well above the previous price tag of about $65 million.

Russia currently provides the only means of getting people to and from the space station, and its ticket prices have soared with each new contract.

NASA Administrator Charles Bolden said if Congress had approved the space agency’s request for more funding for its commercial space effort, the latest contract would have been unnecessary. He is urging full funding of the Obama administration’s 2014 budget request of $821 million in seed money for the commercial crew program.

“Because the funding for the President’s plan has been significantly reduced, we now won’t be able to support American launches until 2017,” Bolden wrote in a NASA blog. It could take longer if Congress does not fully support the 2014 request, he said.