China played a crucial role in persuading Sudan to accept the peace plan over the Darfur issue put forward by former U.N chief Kofi Annan, said Chinese Assistant Foreign Minister Zhai Jun on Wednesday.

Zhai made the remarks at a briefing that came a day after he concluded a four-day visit to Sudan as special envoy of the Chinese government.

"Sudan has accepted in principle the three-phased Annan plan, However, on some of the details, it has reservations," Zhai said. "Sudan is most concerned about its sovereignty and territorial integrity."

The Annan plan proposed deploying more peacekeeping force in Darfur, the western region in Sudan.

During his stay in Sudan, Zhai held meetings with Sudanese President Omer al-Bashir and high-ranking government officials. He also paid a one-day visit to Darfur, touring three refugee camps.

Zhai's trip was China's latest efforts to seek a peaceful solution to the Darfur issue.

Chinese Vice Foreign Minister Dai Bingguo Monday evening talked via telephone with U.S. Deputy Secretary of State John Negroponte on the situation in Darfur.

"China's basic stance is to accomplish peace, stability and development of the Darfur region through negotiations," Zhai said.

China has tried various diplomatic ways, including visits by head of state, special envoy and telephone negotiations, to consult with relevant parties, narrow down their differences and promote dialogues, he said.

Zhai said he is optimistic about the peaceful settlement of the Darfur issue. "It is not necessary to resort to sanctions or other pressures."

He said China has paid close attention to the humanitarian and security situation in Darfur.

China has so far offered humanitarian aid worth 80 million yuan (about 10.4 million U.S. dollars) to the Darfur region, according to Zhai.

China would like to make continued contribution for the peace, stability and development of the region, he said.