Viktor Yushchenko had already vetoed the law, which allows parliamentary factions to nominate Cabinet ministers. But the Supreme Rada overrode the veto with 366 votes Friday, when a former opposition bloc joined the parliamentary majority that supports the largely pro-Russian premier.
"I will not sign it for a number of reasons," Yushchenko said, accusing the parliament of breaking the national unity pact political leaders signed in August in a bid to end the protracted political crisis in the ex-Soviet state.
"We had an agreement with the prime minister [Viktor Yanukovych] that we should draft the law on the Cabinet together as it regulates relations between the president and the Cabinet, among other things."
The parliament also rejected every one of Yushchenko's 42 proposed amendments to the law, which allows the parliamentary majority to nominate a candidate for prime minister if the president fails to make the nomination within 15 days.
The Supreme Rada can now also nominate defense and foreign ministers, which was the president's prerogative under the unity pact.
Yushchenko's opponents managed to overcome the veto, when Yulia Tymoshenko, once the president's closest ally, and her bloc joined the parliamentary coalition dominated by Yanukovych's Party of Regions.
The pro-presidential Our Ukraine party, whose members walked out of the Supreme Rada's session in protest against the law, called the document unconstitutional, "threatening the rights and freedoms of Ukrainians," and said the country was witnessing a serious democratic crisis.
The law can enter into effect in a month. Under Ukrainian law, the parliamentary speaker can sign a bill, approved by two-thirds of the votes in parliament, into law if the president fails to do so within a month.