Brown, who has offered to host the peace talks, discussed the crisis in Sudan's western region with visiting Sudanese Foreign Minister Deng Alor on Tuesday.

"I pressed the Sudanese foreign minister ... about the need for talks to start as soon as possible. I believe it is possible that if talks started, we could also get to a ceasefire and at the same time get to the process of getting a political settlement," Brown told parliament.

Brown said "approaches have now been made to the rebel groups" who he wants to bring together at the negotiating table with the Sudanese government.

"The key thing is to get these talks started," he said.

"That's why the U.N. Secretary General (Ban Ki-moon) is involved, that's why we have offered London as a possible centre for such talks and that's why I'm hopeful, if we can move these forward in the next few weeks, that there is a chance of talks taking place that could bring peace to this troubled area."

Darfur rebels accused the government on Tuesday of bombing areas under their control and said attacks this week showed Khartoum was not serious about seeking peace.

The army denied the accusations.

International experts estimate some 200,000 people have died in five years of war in Darfur, mostly from hunger and disease. Some 2.5 million people have been driven from their homes. Khartoum says only 10,000 have died.

A U.N.-African Union peacekeeping force has so far deployed only one third of its planned strength and failed to prevent attacks that are hindering the world's largest aid operation.

The head of the mission said on Wednesday about 1,600 troops would join the peacekeepers in June as part of plans to deploy 80 percent of the force by year-end.