KIEV, Aug. 29 - Ukraine’s highest court on Wednesday upheld the conviction of former Prime Minister Yulia Tymoshenko for abuse of office, a case that has strained the former Soviet state’s ties with the West.

Tymoshenko was sentenced to seven years in prison in October 2011, when she was found guilty of exceeding her powers while negotiating a gas contract with Russia while she was prime minister.

The contract significantly increased the price Ukraine pays for Russian gas imports that are critical to the country.