New Mexico Gov. Bill Richardson got a bleak assessment of the deteriorating situation in Darfur as he arrived in the Sudanese capital Sunday, hoping to lay the groundwork for peace in the region.

On a 17-hour overnight flight, the former U.S. ambassador to the United Nations worked on a plan to broker a cease-fire, continue the flow of humanitarian aide and persuade Sudanese President Omar al-Bashir to allow U.N. peacekeepers.

On arrival, Cameron Hume, the top U.S. diplomat in Sudan, laid out Richardson's challenge. "I don't think anybody's strategy is working," Hume told Richardson at the airport.

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Richardson, a few advisers and officials with humanitarian groups flew aboard a private jet for the trip arranged by the Save Darfur Coalition. The group asked for Richardson's help in trying to improve the situation in Darfur because he has negotiated successfully with al-Bashir in the past.

Richardson planned to meet with the president on Monday, then fly to Darfur on Tuesday to see rebel leaders.

"I'm not discouraged," Richardson said after the briefing from Hume. "I think we make some measurable progress if we can help the cease-fire and the humanitarian situation and possibly start a united political process that helps the U.N. peacekeeping effort alive."

Hume explained at his hourlong briefing that violence is on the rise in Darfur, making it more difficult for humanitarian groups to travel and distribute aid. He said there have been occasions of rebel groups attacking humanitarian offices, stealing their vehicles and assaulting workers.

Hume said African Union troops that are supposed to be providing protection have slowed patrols, meaning it is more critical that U.N. forces get in the region. So far, al-Bashir has allowed only 20 civilians to be sent in for assistance.

Asked why al-Bashir has permitted the visit of Richardson and activists who have criticized his government, Hume smiled. "Well, first of all he likes the governor," he said. "I think it also has a fact to do with elections in the United States, looking beyond the Bush administration. I don't think they feel threatened by the delegation."

Richardson plans to announce soon whether he will run for the Democratic presidential nomination in 2008. The trip to Sudan helps highlight Richardson's extensive international experience as he prepares for a possible run in a competitive field.

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