Renegade Congolese General Laurent Nkunda says he wants to "liberate" the whole of DR Congo, expanding his rebellion from the east.
Gen Nkunda has told the BBC he is now fighting to "liberate" the whole of the Democratic Republic of Congo.
Until now, he had always claimed to be protecting his Tutsi people against Rwandan Hutu armed groups in the east.
Gen Nkunda said he was walking out of a January peace deal. Recent fighting between his troops and the army has led more than 100,000 people to flee.
DR Congo Defence Minister Chikez Diemu said his statement was "irresponsible".
Gen Nkunda says he wants to expand his theatre of operations for his CNDP forces from eastern DR Congo to the whole country.
The BBC's Africa analyst Joseph Winter says this is a definite change of tone from a man who has always portrayed himself as a defender of his Tutsi people.
"I am calling on the people of Congo to stand up for their liberty, for their freedom," he said.
He says they are under threat from some of those who carried out the genocide of their fellow Tutsis in neighbouring Rwanda 14 years ago.
Such fighting talk will not go down well hundreds of kilometres away in the capital, Kinshasa, where President Joseph Kabila was largely elected on his promise to bring peace to the county after many years of war, says Joseph Winter.
There are some 17,000 United Nations peacekeepers in DR Congo, who will no doubt do their best to prevent the conflict from spreading any further.
The UN helped broker a peace deal in January in the east, which held, more or less, for seven months.
Source: BBC News Thursday 02 October 2008 - Congo rebel 'to expand rebellion'