The Congolese government has signed a peace deal with the M23 rebels it had been fighting until they laid down their arms last month, Kenya's presidential spokesman said on his official Twitter account on Thursday.

"DRC (Democratic Republic of Congo) govt, M23 sign peace agreement in Nairobi," Manoah Esipisu wrote on his account.

M23 are the latest incarnation of Tutsi-led insurgents who have battled Congo's government in its mineral-rich eastern regions for more than two decades.

Congo government spokesman Lambert Mende said three documents were signed at the State House in Nairobi and their provisions include a reiteration of the dissolution of M23 as an armed group.

Other provisions include details of demobilisation and a renunciation of violence as a means of pursuing future claims, he said.

"The document is very clear: there is no blanket amnesty. Those who are presumed to have committed criminal behaviour in terms of international law, war crimes or crimes against humanity will not be reinserted into society," Mende said.