French Polynesia's interim speaker, Hiro Tefaarere, says if Gaston Flosse is a true democrat he will resign as president.
Last week Mr Flosse said he would step down if his Tahoeraa Huiraatira Party failed to win a majority in the Tahiti by-election.
But his party says the result is not official and most assembly members back Mr Flosse's policy for autonomy.
Mr Tefaarere says if Mr Flosse resigns, the assembly can meet within five days.
He says otherwise a no confidence motion will have to be brought when the assembly sits next month.