Yushchenko's Our Ukraine, Tymoshenko's party, and another 2004 Orange Revolution ally, the Socialist Party, are seeking to form a coalition, but disagreements over the distribution of cabinet posts have proven to be a major obstacle.
Tymoshenko insists she should return to the post of prime minister -- from which Yushchenko fired her -- because her party emerged from March's parliamentary elections with more votes than its potential coalition partners.
The pro-Russian Party of the Regions won the elections but failed to secure a majority in parliament.
Yushchenko says he is hopeful a coalition can be formed this month. He is due to meet representatives of the three parties later today.
(Reuters, "Ukrayinska pravda," Interfax-Ukraine)
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