The camp of France's new opposition UMP President, Jean-Francois Cope, says the party's New Caledonian chapter failed to vote properly in the election of a new leader and therefore its result was dropped from the France-wide tally.
The claim was made shortly after the UMP in Noumea issued a statement, saying it didn't want to be taken hostage to the deepening leadership row in Paris.
The losing candidate in the contest, Francois Fillon [fee-yo], challenged Mr Cope's election, saying his victory was based on omitting the result from New Caledonia and two other overseas territories.
The Fillon camp claims that he won by 26 votes in a race which saw 186,000 UMP members cast a ballot.
The Cope camp, however, says New Caledonia's voting process wasn't in line with party rules.
The row has prompted calls for a former foreign minister, Alain Juppe, to become the interim leader.