The Sudanese government has expelled the top Canadian and European envoys on allegations that they were interfering in the country's affairs. As Nick Wadhams reports from Nairobi, the expulsions raise new fears that Sudan may be trying to obstruct peace efforts in Darfur.

The Canadian diplomat, Nuala Lawlor, and Kent Degerfelt of the European Union were labeled persona non-grata on Thursday. The spokesman for Sudan's foreign ministry told the state news agency that the two had "meddled" in Sudan's affairs.

On Friday, the Sudan Tribune Web site quoted a Foreign Ministry official as saying the two had been meeting with Sudanese opposition leaders.

But Canada and the European Union say they were given no reason why the two were expelled. The Canadian Foreign Ministry says Lawlor was standing up for freedom and democracy in Sudan. European Commission spokesman Ian Barber says Degerfelt was not even in the country when he was ordered out.

"What we have is the letter of expulsion," he said. "There's no specific mention of meddling. It's also confirmed that the head of delegation is not in Sudan at the moment, he was already in Europe. He was already in Europe on holiday. That's one of the reasons why the commission is so very surprised by this. Contacts with the Sudanese authorities are ongoing."

The expulsions come at a delicate time. Late last month, the U.N. Security Council overcame Sudan's long-standing objections and approved a 26,000 strong peacekeeping force for Darfur, where some 200,000 people have been killed in four years of conflict.

And envoys from the African Union and the United Nations have been trying to organize peace talks between the government and the various rebel factions. The envoys say they hope the talks will begin in October.

In the United States, White House spokesman Gordon Johndroe said he hoped the expulsions were not bids to derail the Darfur peace efforts. He said Sudan has a history of trying to thwart the will of the international community.

Analysts said it was far too early to tell what exactly the Sudanese government's motivations are.

"In the absence of details, it's very difficult to speculate," said Andebrhan Georgis, the Africa Advocacy director for the International Crisis Group. "I think we just have to see what the Sudanese explanation will be to the Europeans and the Canadians. If we're talking about the deployment of UNAMID. I don't know why the European Union and the Canadians would be picked out of all the other members of the international community."

Canada has been an outspoken critic of the Sudanese government's actions in Darfur. In March, it contributed $48 million to support the African Union force currently stationed in the region.