In the last two weeks the Western-leaning leader, Viktor Yushchenko has twice vetoed the bill which, if it became law, would turn the country into a parliamentary republic and effectively make the president a mere figurehead.
"The issue of signing a bill on the Ukrainian government could either be resolved in the Constitutional Court on a presidential recommendation or in parliament, if Ukraine's president proposes amendments to the bill," Prime Minister Viktor Yanukovych said.
Yushchenko first blocked the bill two weeks ago, but the Supreme Rada overrode his veto with 366 votes when a former opposition bloc joined the parliamentary majority, which backs Yanukovych.
The pro-Russian premier appears to be steadily gaining ground in a power struggle with the president that began with Yanukovych's appointment last August.
Under the constitution, the president must sign the bill into law within two weeks of its submission by parliament. However, Yushchenko's office said last week that as the text of the resubmitted bill differed from that passed by parliament in late December, the deadline does not apply.
The new law allows the parliamentary majority to nominate a candidate for prime minister, as well as defense and foreign ministers, which is currently the president's prerogative.
Yushchenko refused to sign the bill, accusing parliament of violating a national unity pact that political leaders signed in August to end a protracted political crisis in the ex-Soviet state. The document served as a condition for Yushchenko's backing for his former arch-rival Yanukovych as prime minister.
Yanukovych also said Ukraine was not ready to join the European Union, as the country should first of all reach European standards of economic development.
"Ukraine is not ready for swift accession to the European Union," Yanukovych said. "We need to resolve many domestic issues, such as boosting the economy and living standards, as well as harmonizing legislation with Europe's," the prime minister said.
The issue of possible NATO and EU membership has proved a divisive one for Ukraine. Yushchenko has been trying to foster closer ties with the alliances since he came into power on the back of an "orange revolution" in 2004. But his efforts have met with strong resistance from Yanukovych and inhabitants of the country's mainly Russian-speaking eastern and southern regions.
