President Viktor Yushchenko's Our Ukraine Party pulled out of the pro-Western ruling coalition after nine months in power. If the coalition fails to reunite by this weekend, parties will have 30 days to form a new one, to avoid new elections being called.
"I address Yushchenko personally: put aside all emotions, put aside the whole struggle for presidential elections, and return to the democratic coalition within these few days with all your team, without any conditions or ultimatums," the press service quoted Prime Minister Yulia Tymoshenko as saying.
The crisis came to a head when lawmakers from the pro-Russian opposition, the Party of Regions and the Communist Party, backed by the Yulia Tymoshenko Bloc, voted to reduce the president's powers.
Relations between Yushchenko and Tymoshenko have also been strained since the prime minister refused to condemn Russia's actions in the conflict in South Ossetia, and back the president in his support for Georgia.
The pro-presidential faction said it would not return to the coalition unless the Tymoshenko Bloc votes for a parliamentary statement on the situation in Georgia and annuls the results of the vote on 'anti-presidential' laws.
