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Rebels battling soldiers, militiamen on Walikale outskirts

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Walikale is farthest west the rebels have reached

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Fighting follows calls by Congo and Rwanda for ceasefire

(Writes through, adds details about peace efforts in paragraphs

9-12)

March 19 (Reuters) - Rwanda-backed M23 rebels pressed

deeper into Congolese territory a day after Congo and Rwanda's

presidents called for an immediate ceasefire, entering the

outskirts of the town of Walikale late on Wednesday, residents

told Reuters.

Gunfire was ringing out from near the town's Nyabangi

neighbourhood, said Walikale resident Janvier Kabutwa. An army

source, who asked not to be named, said the rebels were battling

soldiers and pro-government militias after overrunning an army

position outside the town in a surprise attack.

Walikale, which is in an area rich in minerals including

tin, is the farthest west M23 has reached during its

unprecedented advance this year.

The town of about 15,000 people sits about 125 km (80 miles)

northwest of eastern Democratic Republic of Congo's largest city

Goma, which the rebels seized in January, and puts them within

400 km of Kisangani, Congo's fourth-biggest city.

The westward advance forced Alphamin Resources ( AFMJF ) last

week to suspend operations at its Bisie tin mine, about 60 km

northwest of Walikale town.

Neighbouring countries and foreign powers have been stepping

up diplomatic efforts to halt what has quickly become eastern

Congo's worst conflict since a 1998-2003 war that drew in

multiple neighbouring countries.

On Tuesday, Congo President Felix Tshisekedi and his Rwandan

counterpart Paul Kagame met in Qatar for their first direct

talks since M23 stepped up its offensive in January.

They issued a joint statement along with Qatar that called

for an "immediate and unconditional" ceasefire.

The United Nations says Rwanda has supported the ethnic

Tutsi-led rebels by providing arms and sending troops.

Rwanda has denied supporting M23. It says its military

has been acting in self defence against Congo's army and a

militia founded by some of the perpetrators of the 1994 Rwandan

genocide.

Congo and M23 had been expected to have their first

direct talks on Tuesday in Angola after Tshisekedi's government

went back on its longstanding refusal to speak to the rebels.

But M23 pulled out of the talks on Monday, blaming

European Union sanctions against some of its leaders and Rwandan

officials.