'Proposal for diversion'
Sidya Toure, an ex-prime minister and leader of Guinea's opposition Union of Republic Forces (UFR), said of Camara's offer: "This does not interest me in the slightest,"
"Moussa Dadis Camara has massacred his own people, and he has lost all credibility. We are not interested in this type of proposal"
Mouctar Diallo, head of the New Forces of Democracy party
"At the moment, we are more interested in burying our dead."
Earlier Mouctar Diallo of the New Forces of Democracy party also dismissed Camara's proposal as a "diversion".
"Moussa Dadis Camara is no longer credible to lead a transition [to democracy]," Diallo said.
"He has massacred his own people, and he has lost all credibility. We are not interested in this type of proposal."
Camara's National Council for Democracy and Development (CNDD), which seized power in a bloodless coup last December, called for an African leader to be appointed as a mediator in talks on a unity government.
Carrot and stick
It also proposed UN-backed investigations into the violence on Monday, for which Camara has blamed uncontrolled army elements, and into a February 2007 crackdown on opponents of Lansana Conte, the late president, in which more than 180 died.
Despite the unity call, Camara has taken a tough line on opponents since the unrest, banning all meetings and describing them as "subversive" and pledging to punish any opposition "trouble-makers".
Senior opposition figure Cellou Dalein Diallo, who suffered five broken ribs in Monday's incident, was prevented by the military government from leaving the country late on Wednesday to receive medical treatment in France, an aide told Reuters news agency.
Monday's violence, the worst since the CNDD came to power, drew broad international condemnation.
Former colonial power France said it had cut military co-operation with Guinea and would discuss other measures with European partners.
The African Union has given Camara until the middle of October to confirm he will stay out of presidential elections due on January 31, warning of sanctions if he misses that deadline.