KINSHASA - Democratic Republic of Congo said on Friday it wants the mandate of the U.N. peacekeeping mission in the country strengthened so it can eliminate rebel groups in its lawless east, as called for by regional leaders seeking to end cycles of conflict.

The statement came after Britain joined the United States and the Netherlands as donors who have cut or suspended aid to Rwanda in the wake of a U.N. report that Kigali is backing rebels in fighting that has displaced 470,000 since April.

Rwanda has rejected the report, saying donors were acting on "flimsy evidence".

As part of efforts to diffuse tension between Kinshasa and Kigali, veteran foes during years of conflict in Congo, regional leaders brokered a deal for a "neutral force" to be set up to take on Congo-based rebel groups.

No details have been given on the plan but, in theory, the force would target all rebels, including the anti-Kinshasa M23 rebels and Rwandan Hutu FDLR fighters Kigali says are a threat.

The fighting in North Kivu province comes after three years of generally improved relations between Congo and its tiny but militarily powerful neighbour, which has said previous military actions in Congo were justified by the threat posed by Rwandan Hutu rebels who have been based there since a 1994 genocide.

"We know very well that if we start from scratch it will take a very long time, that's why we're suggesting the solution of transforming parts of MONUSCO," said Lambert Mende, a spokesman for Congo's government, referring to the U.N. mission.