"An agreement signed between Our Ukraine and the Yulia Tymoshenko Bloc in February does not foresee any broad coalition, no alliance with the Party of Regions in a new parliament," Vyacheslav Kyrylenko said.
Earlier, Mykola Tomenko, deputy speaker and a leader of the Yulia Tymoshenko Bloc (YTB), said his party would like to receive guarantees from Our Ukraine that it will not build a coalition with the Party of Regions.
"We will only create a coalition of democratic forces, and if democratic forces win an early parliamentary election, it will form a new Cabinet of Ministers," he said.
Our Ukraine has accused the ruling coalition of foot-dragging on negotiations in an ongoing political crisis with the aim of disrupting early parliamentary elections.
It said in a statement posted on its official Web site that the party is always ready for dialogue, but will not allow anyone to use it to plunge the country into a prolonged parliamentary crisis.
Russia reiterated its readiness to mediate the ongoing political conflict in Ukraine.
"If all parties concerned are interested in Russian mediation, I am convinced that there will be a positive response from Russian politicians," Russian Deputy Foreign Minister Grigory Karasin said Friday.
Prime Minister Yanukovych asked the EU and Russia Thursday to act as international mediators in talks to settle the crisis in Ukraine.
"The neutral position of our strategic partners is not conducive to a resolution of the current political conflict," Yanukovych said, adding that could exacerbate the civil confrontation and split the country.
Russia said earlier it may consider mediation in Ukraine if the former Soviet republic formally requests it.
But the EU said Friday it has not received a formal request from Ukraine to mediate the crisis.
A month-long political standoff between the opposition and pro-premier coalition neared an end Friday when Viktor Yushchenko and Viktor Yanukovych agreed to hold early elections. The opposition insists that the elections be set for July, while the ruling coalition is pushing for the fall.
Ukraine's parliamentary speaker called on the pro-government coalition Friday to put on hold negotiations with President Yushchenko until he ends pressure on Constitutional Court judges.
On Thursday, Viktor Yushchenko dismissed Constitutional Court judge Volodymyr Ivashchenko, having earlier dismissed another two judges, Syuzanna Stanyk and Valeriy Pshenichnyi, for purported breach of oath.
"All formal and informal negotiations with the president should be suspended until the status of the Constitutional Court is restored and until the president revokes his unlawful decrees with respect to the judiciary," Oleksandr Moroz said.
The Constitutional Court is currently considering the validity of the presidential decree dissolving the Ukrainian parliament and calling snap parliamentary elections.
Constitutional Court judges said Thursday the pressure on them is untenable.
The Supreme Rada adopted Friday an appeal to the Parliamentary Assembly Council of Europe (PACE) chairman, EU heads of state and government, and European MPs, accusing President Yushchenko of seeking to usurp power.
It also formally asked the president to submit his annual state of the nation address to parliament as a matter of urgency, passing a corresponding resolution stating in part that there was no such address in 2006 and none so far this year.
Ukraine's opposition said Thursday it is ready to return to parliament and pass all necessary laws to settle the crisis.
President Yushchenko said if Ukraine's political forces fail to reach a compromise and overcome an ongoing crisis, a decision on snap parliamentary elections will be made by the National Security and Defense Council.
"If no results are produced, I will have to call an emergency meeting of the National Security and Defense Council, which will address these matters," he said.
Pro-presidential factions quit the disbanded parliament April 19.
Yushchenko said he is ready to "temporarily" suspend his decree disbanding parliament as it meets for a plenary session, but did not provide details on the legal status of his decree.
Opposition leader Yulia Tymoshenko has said June 24 is the only legitimate date for a parliamentary election, as established by presidential decree, but said the president is ready to move it back to July 8 if representatives of all political forces meet in parliament for one day and reach a compromise solution.
Tensions in the ex-Soviet state have persisted since Yanukovych came to power as prime minister after the March 2006 parliamentary elections, following his defeat by Yushchenko in the 2004 presidential election
