The pro-independence politician Roch Wamytan has been elected as the president of New Caledonia's Congress.
Mr Wamytan of the Caledonian Union secured 29 of the 54 votes after getting the backing of the three members of the new Pacific Awakening party.
He defeated Magali Manuhalalo of the anti-independence Caledonia Together party who won 25 votes.
Pacific Awakening was tallied as being part of the anti-independence bloc after the provincial elections 12 days ago.
However, the party, which represents mainly ethnic Wallisians and Futunians, decided to endorse Mr Wamytan over Ms Manuhalalo, who is also an ethnic Futunian.
The Congress vote has gone against this week's deal struck within the anti-independence camp which had earmarked the Congress presidency for Philippe Michel.
This was agreed after the big winner of the provincial election, Sonia Backes of the Future with Confidence, assumed the presidency of the southern province.
The deal also provides for the presidency of the collegial government to go to Future with Confidence.