France is expected to announce who of the two kings installed in Wallis at the weekend is the legitimate one.
The decision by the territory's prefect has to be published in the official journal and confirm who was enthroned properly.
The king and the chiefs are part of the administration and on the payroll of the French republic.
France has already sent extra police from New Caledonia amid fears of worsening tension between the rival sides.
The installation of Tominiko Halagahu as the new king of Uvea was followed by a rival council of chief making Patalione Kanimoa the new king in a ceremony at the royal palace on Sunday.
The weekend events ended a two-year vacancy of the throne and followed a week of acrimony after Tominiko Halagahu had been proposed to be the new monarch.
Rival royal families occupied the royal palace in protest .
After Tominiko Halagahu was installed in a surprise ceremony in his district on Friday, the families occupying the palace moved to install Patalione Kanimoa as their king.
A Wallisian customary chief in Noumea said Patalione Kanimoa was the only legitimate monarch because his installation was performed in line with the sacred procedure.