The faction, led by former premier and heroine of the 2004 "orange revolution," left the 450-seat Supreme Rada calling for new elections in protest against the formation of a new coalition led by its arch rival, the Party of Regions.
But Yevhen Kushnarev, deputy head of the pro-Russia Party of Regions faction, said the move would have no impact. "It will not affect our work at all," he said.
The Party of Regions, which won the largest share of vote in the indecisive March elections and is leading a new parliamentary coalition with the Socialists and Communists, has been seeking to persuade members of pro-presidential Our Ukraine bloc to join the coalition.
However, Kushnarev said, "We have not yet succeeded in expanding the majority coalition."
Our Ukraine, the Socialists and Tymoshenko's bloc formed a West-leaning coalition on June 22 but it collapsed when some Socialists defected and formed a new "anti-crisis" coalition with the Party of Regions and the Communists.
Kushnarev said a broader coalition had been discussed at consultations between the "anti-crisis" coalition and Our Ukraine. The coalition offered Our Ukraine ministerial posts in a future government.
But the pro-presidential party insisted on dissolving the current coalition and forming a new one.
"We cannot do this, and that's it," Kushnarev said.
