Paris  - The run-off vote to chose a new leader for France's Socialist Party was too close to call early Saturday as the losing Socialist candidate in the 2007 French presidential election, Segolene Royal, sought another shot at the country's top job.

If she beats her opponent, Lille Mayor and former labour minister Martine Aubry, she would take a big step toward securing her party's nomination to again take on President Nicolas Sarkozy in the 2012 presidential election.

But Aubry's supporters said they believed she had won the vote with 50.5 per cent of the ballots.

"We won't let victory be stolen from us," the Royal camp said.

The party did not indicate when it might be able to announce Francois Hollande's successor.

Overseas votes in Friday's internal party balloting could eventually decide the outcome, a Hollande spokesman said.

It became known early Friday that the Socialist Party would be led by a woman for the first time in its history after the three-candidate race was reduced to two when European Parliament deputy Benoit Hamon failed to make the runoff.

Royal, 55, came out on top in the first round with 43.1 per cent of the vote to 35.4 per cent for Aubry, 58.

Hamon, who received 22.8 per cent, urged his supporters to vote for Aubry, making her the favourite going into the run-off.

In 2007, Royal became the first Frenchwoman to make it to the second round of the presidential election, but she was soundly beaten by Sarkozy.

The party, which has 230,000 members, is the strongest opposition party in France. (dpa)