Kinshasa - The main opposition party in the Democratic Republic of Congo on Thursday accused President Joseph Kabila of "high treason" over the "grave crisis" in the east, where the army is struggling to put down a rebellion.
Hundreds of Rwandan special forces troops deployed in the eastern DRC pulled out last week after the Rwandan defence ministry announced it was scrapping a joint mission with DRC's army to fight rebel militia there.
The Union for Democracy and Social Progress (UDPS), DRC's largest opposition party, said on Thursday that Kabila's government should never have let Rwandan troops into the country.
"The willing deployment on national territory of a foreign army without the knowledge of the Congolese people constitutes the proven complicity of Mr Kabila in the crisis in the east," said UDPS official Bruno Mavungu Pwati, adding the deployment made the president guilty of "high treason".
He made an "urgent appeal" to the nation to "put an end to the political adventurism of Mr Kabila and his accomplices".
On Monday a coalition of opposition parties called on parliament to impeach Kabila for treason over the conflict in the east.
The chronically unstable region has been hit hard by a new rebellion by army defectors who have formed an armed group called the M23, whose members are former fighters in an ethnic Tutsi rebel movement integrated into the military under a 2009 peace deal.
A UN report in June accused Rwanda of backing the rebels, causing a surge in tensions with neighbouring DRC. Kigali denies the charge, and has been in talks with Kinshasa to set up a "neutral force" to tackle the unrest.
Fighting in the region has displaced more than 220 000 people since April, and more than 57 000 others have fled to Rwanda and Uganda.