"I think that the Cabinet will be approved [by parliament] today," said Oleksandr Moroz, who also leads the Socialist Party in the majority coalition.
The country's lawmakers have gathered in the Supreme Rada, and are expected to confirm Party of Regions leader Viktor Yanukovych as prime minister. The pro-Russian leader's nomination received the backing of his former rival President Viktor Yushchenko on Thursday after four months of political turmoil.
The Party of Regions, along with the Socialist and Communist parties, joined forces with the pro-presidential Our Ukraine bloc on Thursday, to form a new "grand coalition" in the 450-seat legislature.
Yanukovych backers from the Moscow-leaning camp are expected hold most ministerial positions in the new Cabinet, but the president has the right to nominate the defense and foreign ministers.
The Supreme Rada speaker said parliament would stay in session until the Cabinet is fully formed, regardless of how long it takes.
Moroz also denied media reports that President Yushchenko may withdraw his nomination of Yanukovych for the premiership.
