The United States hopes that after releasing former Interior Minister Yuriy Lutsenko, the Ukrainian authorities will also release former Prime Minister Yulia Tymoshenko, U.S. Ambassador to Ukraine John Tefft has said.

When asked whether U.S. and European diplomats will insist on the release of Tymoshenko, Tefft said: "I think so. If you read a statement by the White House and the State Department, it said that this is the first step, and we expect that there will the continuation, and Tymoshenko will soon be released, like Lutsenko."

He also said that he has high expectations regarding further developments in Ukraine.

"I'm an American, I'm an optimist, and I always have high expectations for Ukraine," he said.