France has commended the return of "constructive dialogue" between political parties in the troubled Comoros, with the aim of fixing a date for presidential elections. Crisis talks in the Indian Ocean archipelago resumed after the president's term expired at midnight on Wednesday.

The political tensions in the Comoros stem from President Ahmed Abdallah Sambi extending his mandate by one year through a constitutional referendum.

Tensions deepened after the parliament moved to hold presidential elections for the governors of the three autonomous islands, Grande Comore, Anjouan and Moheli, in November 2011.

The decision upset residents of Moheli, which was due to take the rotating presidency from Sambi under a power-sharing deal that was brokered in 2001.

Moheli islanders are demanding their turn at the presidency and protest marches have been growing in scale and intensity on the island during the last months. Fresh rioting broke out on Wednesday after Sambi appointed a new interim government.

France's Foreign Affairs Minister Bernard Kouchner called on all the Comoran players to "reject all provocation" at disabling the crisis talks, "including by the island of Moheli, which is again showing regrettable acts of violence".

The minister thanked "renewed international efforts driven by the African Union" for the return to negotiations on 23 May between the Comoran parties.

"France encourages all the Comoran political parties to take responsibility and make the necessary compromises, with the aim of fixing a date that is realistic and will allow for the organisation of credible elections," said Bernard Valero, a spokesman for Kouchner.

Several opposition forces on the other two islands, Grande Comore and Anjouan, also questioned the legitimacy of the constitutional referendum in which Sambi's term was extended, saying the change also should have been approved by each one of the union's three islands.

The AU, which brokered and guarantees the 2001 deal, says it is close to reaching a new deal between President Sambi and the opposition that would include an election in November.

The Mohelian opposition has indicated it is willing to wait till November, but only if the 2001 rotation deal is respected and the next Union President is elected among Mohelians.