MONTREAL - A public spat has erupted over the leadership of the separatist Parti Quebecois, putting more pressure on embattled PQ Leader Andre Boisclair to submit to a confidence vote.

The spat has divided the party and pitted Boisclair against his federal counterpart, Bloc Quebecois Leader Gilles Duceppe.

A prominent party member accused Boisclair on Sunday of a lack of judgment for a vitriolic attack on Duceppe, making the rumoured rift very public.

"It's a flagrant lack of judgment," Yves Michaud said.

He said Boisclair should question whether he's in the right place in the sovereigntist party.

"Mr. Boisclair does not run the party," Michaud said. "It's the party members who run the party and it's they who will decide."

Boisclair has been under fire over the party's dismal performance in the recent provincial election, where the PQ dropped to 36 of the 125 seats in the national assembly and lost official opposition status.

Rumour is rife that Duceppe is poised to make a bid for the PQ leadership - rumours that prompted an outburst from Boisclair in a recent television interview.

The embattled sovereigntist leader said elements of his own party are plotting to replace him with Duceppe.

Duceppe has denied he's preparing to jump to provincial politics.

Michaud said the accusations are not based on fact. Boisclair is desperate after his poor election performance, he said.

"To accuse a brother in arms, you have to put your cards on the table," Michaud said. "If there are names, name them."

He called Boisclair's statements "childish."

"One can understand that Mr. Boisclair is obviously disoriented after the defeat on March 26," said Michaud, who first called for Boisclair's resignation before the provincial election campaign even began.

He said the PQ is in crisis because of both the messenger, Boisclair, and his message, which Michaud said has abandoned the party principles on language and a separate Quebec nation.

He called on Boisclair to submit himself to a confidence vote before the end of the year.

The PQ executive has offered Boisclair its support but proposed moving the party convention ahead by a year, to September 2008, when Boisclair would face a leadership review. Riding presidents will make a final decision this month.