A Kiev court will hand down its verdict on Tuesday in the corruption trial of former Ukrainian Prime Minister Yulia Tymoshenko.
Prosecutors are seeking a seven year jail term, accusing her of paying too much in a 2009 gas deal with Russia.
EU officials warn it could jeopardise President Viktor Yanukovych’s goal of closer ties with Brussels.
But the former PM’s critics say the EU should not interfere and that Tymoshenko has a case to answer.
Tymoshenko’s camp say the case is just a political show-trial to sideline the president’s bitter rival.
Analysts say that Moscow also has a lot at stake.
Vitali Bala, an analyst at the AMC think tank in Kiev, said Russia won’t put pressure on Ukraine not to jail Tymoshenko.
He said “If the court cites the gas deal as the reason for doing so, it could harm Russian interests further down the line.”
EU diplomats also say that jailing Tymoshenko could also scupper planned free trade agreements between Ukraine and the 27-member bloc.
As our correspondent Sergio Cantone explains, both sides are awaiting this verdict with baited breath:
“They feel that it’s a judgement that will shape Ukraine’s future alliance, and even its future foreign policy. If a guilty verdict is handed down, it could see Ukraine drift away from the EU.”