By Sam Cage and Luiza Ilie
BUCHAREST (Reuters) - Romania's Constitutional Court on Thursday delayed ruling on whether a referendum to impeach the president was valid, an unexpected twist that extends a damaging political crisis.
The court had been expected to invalidate Sunday's referendum after official data showed that while a majority of those voting wanted to dismiss the president, turnout did not reach a required 50 percent threshold.
However, the court postponed its decision on President Traian Basescu's impeachment until September 12, extending the political uncertainty and pushing the leu 0.4 percent lower against the euro.
Efforts by center-left Prime Minister Victor Ponta to oust his center-right rival have hamstrung political decision-making and drawn severe criticism from the European Union which expressed concerns about the rule of law in Romania.
The row has also raised doubts over an International Monetary Fund-led aid deal, sending the currency to record lows. Dealers said the leu would probably test all-time lows around 4.65 per euro while the situation remains unclear.
After meeting for some 13 hours on two successive days, the court said it needed more time because it had received conflicting data on the size of the electorate. It asked the government to send it the most up-to-date electoral lists by August 31.
The co-leader of Ponta's Social Liberal Union (USL) party, Crin Antonescu, will serve as interim president until the court makes its ruling.
Final results showed 88 percent of those who voted in the referendum wanted rid of Basescu, unpopular for his austerity policies and perceptions of cronyism.
Members of Ponta's party have suggested the true number of Romania's total electorate, based on new preliminary census data, was smaller than the figure used and that, using that number, turnout did actually beat the threshold.
The IMF is currently in Bucharest to review Romania's deal, an agreement that is important reassurance for investors.
The IMF had delayed its review until after the referendum and its officials could raise concerns about delays to economic reforms, privatizations and about the budget deficit, which is expected to expand in the second half of this year.
CALLS FOR RESIGNATION
Ahead of the referendum, Ponta's government had sought to trim the Constitutional Court's powers and even threatened to replace judges before concerted pressure from the EU and United States forced it to back down and accept the court's ruling on the minimum turnout.
Ponta called on Basescu to resign after the vote, citing the 88 percent who wanted him impeached. The president said there was a majority of voters who did not want him removed from office and he has refused to step down.
The court validated nationwide local elections held in June that were based on the same electoral data used for the referendum and Laura Stefan, a legal specialist at the Expert Forum think-tank, said any changes to the electorate figure would include only removing the dead and those who voted multiple times.
"The court was scared by the importance of the decision it has to make and ... the pressure it's been getting," Stefan said. "I don't think this will change the results very deeply."
One of the nine Constitutional Court judges, Aspazia Cojudges, told reporters her inclination was to annul the referendum. "Everything was based on fake data," she told reporters.
(Editing by Robin Pomeroy)