KHARTOUM - Sudan's junior partners in government will boycott parliament until a package of democratic laws is passed, a senior official said on Sunday, stoking tensions ahead of elections next year.

The northern National Congress Party (NCP) and the southern Sudan People's Liberation Movement (SPLM) signed a 2005 peace deal ending more than two decades of civil war. But delays over implementation have led to fears of reignited conflict.

More than 20 opposition parties said they would boycott Sudan's first multi-party vote in 24 years if democratic laws, including reform of the powerful national security forces, were not passed this parliamentary session.

The SPLM said last week it would keep up the boycott until Sunday, October 25. But with little progress, Arman said the walk out would continue.

The NCP criticised the boycott, questioning how it would help parliamentary discussions on the laws. The NCP has a majority of seats in the legislature.

With elections less than six months away, the SPLM and opposition parties say the NCP has showed no political will to pass laws that they view as essential for free elections.

U.S. President Barack Obama unveiled a new strategy last week offering Sudan incentives for implementing the 2005 deal but warning of penalties if Khartoum stalled.