Yulia Tymoshenko, President Viktor Yushchenko's first prime minister and ally on the streets in the 2004 popular protests known as the "orange revolution", was the only leader of a major political movement who refused to sign Thursday a national unity agreement aiming to end the country's protracted political crisis.
And Oleg Bilorus said the faction would form a firm opposition to the new government, which should be led by Tymoshenko's long-time rival, Viktor Yanukovych, if he is confirmed as prime minister as expected in a Friday vote.
"We will form a systematic, constructive and strong opposition, which will make use of all existing European models of the parliamentary struggle, including the formation of a shadow Cabinet," Bilorus said.
Bilorus said that the bloc, which has 129 seats in the 450-member Supreme Rada, would not attend the Rada's sessions in a protest against the formation of the "grand" coalition and Yushchenko's decision to back Yanukovych for the prime minister's job.
The bloc was the leading force in the first parliamentary coalition to emerge after the March 26 elections, but the alliance collapsed when the Socialists defected to join Yanukovych's Party of Regions.
He said the faction would not take part in the vote on Yanukovych for the prime minister's post, but would appear on the Rada's sidelines during ballots to elect members of the country's Constitutional Court.
