Some 250,000 people have fled their homes and aid agencies are struggling to help them.
Some fled the countryside for Goma but others have since returned, as there is not enough food or shelter for them.
Some fled the countryside for Goma but others have since returned, as there is not enough food or shelter for them.
Earlier, the French foreign minister called for the mandate of the 17,000-strong UN peacekeeping force in DR Congo to be strengthened.
Earlier, the French foreign minister called for the mandate of the 17,000-strong UN peacekeeping force in DR Congo to be strengthened.
UN peacekeeping chief Alain Le Roy, visiting Goma, said the UN mandate was currently to "protect civilians and to support the army in disarming rebel forces".
UN peacekeeping chief Alain Le Roy, visiting Goma, said the UN mandate was currently to "protect civilians and to support the army in disarming rebel forces".
"Our mandate is not to defend cities," he told the BBC's Network Africa programme.
"Our mandate is not to defend cities," he told the BBC's Network Africa programme.
On Monday, a first UN convoy carrying medical supplies was given safe passage into rebel-held territory, where aid agencies have described the humanitarian situation as dire.
On Monday, a first UN convoy carrying medical supplies was given safe passage into rebel-held territory, where aid agencies have described the humanitarian situation as dire.
'Waging war'
During his planned visit this weekend, Mr Ban plans to hold talks with both Congolese President Joseph Kabila and Rwandan President Paul Kagame, whose forces are accused of backing the rebels.
"The conflict along the Rwanda and Congolese border has gone on too long and [with] catastrophic consequences," he said.Enlarge Map
The UN chief has also named former Nigerian President Olusegun Obasanjo as his special envoy to the region.
The DR Congo government refuses direct talks with rebel leader Gen Laurent Nkunda, saying he should stick to a peace deal signed in January.
But a rebel spokesman said this amounted to "waging war" and have threatened to topple the government.
French Foreign Minister Bernard Kouchner has called for both the mandate and the numbers of the UN force in DR Congo - Monuc - to be beefed up.
"We need different soldiers, and different rules of engagement," he said after briefing his EU counterparts about a weekend visit to the region.
Monuc is the biggest UN peacekeeping mission in the world, but is struggling to contain the conflict.
Mr Le Roy said he hoped the UN Security Council would listen to a request made a month ago to increase the UN troops.
For now, Monuc's priority was to reinforce itself in North Kivu.
"Our priority is Goma - to make sure Goma is a red line," he said.
"Then we strengthen our presence on the road between Goma and Rutshuru to make sure there is clear access to humanitarian goods."
Camps empty
Following a meeting of EU foreign ministers in France on Monday, Mr Kouchner said the force needed "more of an offensive capability".
He said the peacekeepers' rules of engagement were "insufficient" and "very restrictive", and did not rule out sending EU troops to DR Congo as well.
UN troops escorted Monday's aid convoy to Rutshuru, a rebel-held town 75km (45 miles) north of Goma.
It carried medical supplies and water purification tablets, and the UN said food convoys were expected to follow.
Aid workers found refugee camps that had held tens of thousands were virtually empty. Many people are believed to have fled into the forests around the camps fearing further violence.
The recent rebel offensive was exacerbated by a wave of killing, looting and raping by retreating Congolese soldiers.
History of genocide
Meanwhile, the Associated Press news agency quoted a UN official as saying that Rwandan forces fired tank shells into DR Congo during last week's fighting.
Rwandan officials had denied the allegations, spokeswoman Sylvie van den Wildenberg said, "but we saw it. We observed it."
If confirmed, it would be the first time the UN has publicly accused Kigali of being overtly involved in the conflict.
Although Rwanda has twice invaded its much larger neighbour in recent years, it has repeatedly denied accusations its forces were actively supporting Gen Nkunda.
UK Prime Minister Gordon Brown has said the international community must "not allow Congo to become another Rwanda".
In 1994, 800,000 people died in Rwanda's genocide, which is seen as the origin of the current conflict across the border.
Gen Nkunda says he is fighting to protect his Tutsi community from attack by Rwandan Hutu rebels, some of whom are accused of taking part in the genocide.
There have also been accusations of collusion between DR Congo's army and Hutu guerrillas.
