Khartoum has declined to issue visas for senior US, British, and French diplomats planning to conduct a fact-finding mission in Darfur.
UN diplomatic sources told Reuters on Tuesday that Deputy UN Ambassadors Peter Wilson of Britain, David Pressman of the USA, and Alexis Lamek of France intended to visit Darfur in January.
They said that Sudan's failure to grant visas to the diplomats was a further sign of Khartoum's increasingly confrontational approach to the UN and the West concerning the UN-AU peacekeeping mission in the war-torn region of Darfur.
Sudan's UN mission did not respond to requests for comment, Reuters correspondent Louis Charbonneau noted.
A British diplomat confirmed that Wilson had planned to lead the trip, and said that Britain is interested in improving Unamid, and gauging the conditions for the mission's roughly 19,000 peacekeepers.
Khartoum is demanding that 15,000 Unamid troops be withdrawn by the end of 2015. Yet, Max Gleischman, spokesman for the US mission to the UN, said that Unamid still has important role to play in protecting civilians in the war-torn western region of Sudan.
"We vehemently oppose any effort to draw down or close the mission prematurely," he said. "We have seen more displacement in Darfur in the last year than in the history of the decade-long conflict."
He added that Khartoum is obstructing Unamid's work on a daily basis.