Rwanda-backed rebels claimed they captured eastern Congo’s largest city, Goma, early Monday, as the United Nations described a mass panic among its 2 million people and Congo’s government said the rebel advance was a “declaration of war.

The Democratic Republic of Congo and Rwanda have broken off diplomatic ties after an escalation in fighting in eastern Congo near the border with its neighbour.

United Nations chief Antonio Guterres on Sunday urged Rwanda to withdraw its forces from the eastern Democratic Republic of Congo where fierce fighting raged as Kigali-backed fighters closed in on the major city of Goma.

Rwanda said Sunday that clashes in the eastern Democratic Republic of Congo, where Kigali-backed fighters are locked in battle with the Congolese army, required it to maintain a "sustained defensive posture".

The Democratic Republic of Congo on Sunday called for the United Nations to sanction Rwanda, accusing its neighbour of issuing a "declaration of war" by sending more troops over the

France and Britain have called on Rwanda to address accusations of supporting the M23 rebels in recent conflicts near Goma, in eastern Congo. At a U.N. Security Council meeting, both countries urged Rwanda to withdraw its troops from Congo territory amid escalating tensions.

M23 fighters have been pressing to capture strategic eastern city for months and intensified offensives in recent days.

Army spokesman Ronald Rwivanga said "five civilians have died and 25 severely wounded and more were lightly injured" on the outskirts of Rwandan border town Gisenyi.

In an op-ed in the Financial Times on Sunday, Jason Stearns, author of The War That Doesn’t Say Its Name: The Unending Conflict in the Congo, accused the west of soft-peddling on Rwanda, which he called “the main instigator of the M23 conflict”.

Congolese government spokesperson Patrick Muyaya said Kinshasa wanted to prevent "carnage," with Rwanda's forces in the east of the country. It comes after the M23 group claimed to have taken the city of Goma.

The Democratic Republic of Congo has formally recalled its diplomats from Rwanda and demanded that Rwanda halts its diplomatic activities in the Congolese capital within 48 hours. The directive came through a letter verified by a foreign ministry official,