By Yassin Kombi and Sonia Rolley GOMA, Democratic Republic of Congo (Reuters) -President Paul Kagame said Rwanda was ready for "confrontation" as he rejected criticism over his backing for M23 rebels who were pushing south on Thursday in eastern Democratic Republic of Congo after capturing the major city of Goma.

Local sources said Kigali-backed fighters were advancing on a new front and had seized two districts in South Kivu province, after the rebel group’s capture of most of Goma, the capital of North Kivu.

Regional tensions spiral as peacekeepers killed in fighting following Rwandan-backed M23 rebel group offensive

Meanwhile, Rwandan President Paul Kagame said his country will “deal” with any confrontation from South Africa after 13 of its peacekeepers in eastern Congo were killed.

The rebels, which Rwanda denies supporting, have long been funded at least in part by the illicit mineral trade.

Many Congolese see the rebel advance as an invasion of their country by a foreign power in an attempt to seize land and Congo’s valuable rare minerals.

M23 rebels, with support from Rwandan troops, marched into Goma earlier this week and are now advancing south toward Bukavu.

The Rwanda-backed armed group M23 vowed Thursday to "continue the march of liberation" to the DR Congo capital Kinshasa, as its fighters made further advances in the mineral-rich east of the country.

Reuters quoted the spokesperson as saying that the UN is deeply concerned by these developments, which are backed by "credible reports."

The Rwanda-backed armed group M23 vowed on Thursday to march on the DR Congo capital, Kinshasa, as its fighters made further advances in the mineral-rich east of the country. "We will continue the march of liberation all the way to Kinshasa,

Democratic Republic of Congo President Felix Tshisekedi has vowed “a vigorous and coordinated response” against a rebel alliance that has besieged swaths of the nation’s mineral-rich east and forced hundreds of local troops and foreign mercenaries to surrender.