(Reuters) -Rwanda-backed M23 rebels pressed on with their offensive in eastern Congo a day after the Congolese and Rwandan presidents called for an immediate ceasefire, entering the outskirts of the town Walikale late on Wednesday,

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.

The Rwanda-backed rebels who captured key areas of Congo's mineral-rich east said Monday they were withdrawing from peace talks this week with the Congolese government, saying that international sanctions on the group's members have undermined such dialogue.