Bodies are decomposing on the streets of Goma that have not yet been collected, with hundreds of thousands displaced in the region after fighting between Rwanda-backed rebels and Congolese forces.

Rwandan-backed M23 rebels in Democratic Republic of Congo are seeking to advance south towards Bukavu, the capital of South Kivu province, in an attempt to expand their area of control in the country's east after capturing the city of Goma.

Rebels occupying the eastern Democratic Republic of Congo city of Goma have declared a cease-fire but the government dismissed the pause in the fighting as a ruse aimed to head off growing international concern.

Rwandan-backed M23 rebels say they are now in control of the key eastern Congolese city of Goma. Their fighters continue to claim more territory in one of the world's most mineral-rich territories.

France expresses its solidarity regarding the Democratic Republic of Congo and condemns actions by Rwanda in the country, French Foreign Minister Jean-Noel Barrot said on Monday.

The M23 militia, funded and directed by Rwanda, said it had seized the city of Goma, terrifying its people, many of whom sought shelter there after fleeing the rebel advance.

A rebel group that claimed to have captured the city of Goma in the eastern Democratic Republic of Congo last week has called for an immediate humanitarian ceasefire, after fighting with the Congolese military has left hundreds of people dead.