A leading Sudanese opposition party says it is refusing a call by protest leaders for a two-day general strike, in a sign of divisions within the pro-democracy movement that is challenging military rule in Sudan.

The opposition Umma Party said Sunday it opposes the "preparations and timing" of the strike.

The party is a member of the Forces for the Declaration of Freedom and Change, an umbrella group representing protesters and opposition parties in the negotiations with the ruling military council.

The FDFC said the nationwide strike would begin Tuesday. Protest leaders are hoping to force the military, which ousted the autocrat Omar al-Bashir from power in April, to transfer power to a civilian-led authority.