Members of one of the main Congolese rebel groups have arrived in the capital, Kinshasa, to take up their posts in the transitional government.
Mr Bemba says it is 'the end of the phase of the war' in DR Congo
The new administration of national unity was named by President Joseph Kabila on Monday.
The Congolese Liberation Movement, (MLC) has seven ministers and four deputy ministers.
Its leader, Jean Pierre Bemba, is one of the four vice-presidents in the new administration.
Mr Bemba told the BBC's Network Africa programme that his movement believed the war in the DR Congo had come to an end.
The fight against corruption, tribalism and democracy will be at the forefront of the group's new battle
Jean Pierre Bemba
He said the MLC would now become a political party and prepare itself for elections, which are due to be held in two years time.
"The fight against corruption, tribalism, for fundamental rights and democracy will be at the forefront of the group's new battle," Mr Bemba said from his stronghold in the north-eastern town of Gbadolite.
Mr Bemba also said there would be no immunity for atrocities committed during almost five years of war.
DR Congo was plunged into war in 1998, when rebel groups backed by Rwanda and Uganda, rose up against the government of then President Laurent Kabila.
The conflict drew in four other African nations.