The press service of pro-presidential Our Ukraine said the party had received a letter on Monday morning signed by the head of the Socialist Party, Vasyl Tsushko, informing them of the party's official exit from the coalition, which collapsed last Thursday.
The party registered the document with parliament on Friday, the press service said.
The Socialist Party's coalition with the Yulia Tymoshenko Bloc and Our Ukraine broke down Thursday following the surprise election of Socialist Oleksandr Moroz as parliamentary speaker. President Viktor Yushchenko then called for another coalition to be formed so that he would not have to dissolve the assembly.
On Friday, the Party of Regions, which won the largest number of votes in the March 26 election, but not enough to form a government on its own, teamed up with the Communist Party and the Socialists to form a new parliamentary coalition and had its leader nominated as prime minister.
The party said that the new coalition opened a path toward a return to normal life in Ukraine and to reunifying the country, which has been split with the west leaning toward European integration and NATO membership, and the east looking toward closer ties with Russia.
