President Omar al-Bashir has called for a national dialogue to try to end conflicts in border regions and to right its ailing economy.
The government says the talks must take place in Sudan.
"We are ready to offer the required guarantees for armed groups to attend" the national dialogue, First Vice President Bakri Hassan Saleh said at a press conference.
"We are ready to freeze the sentences" against rebel leaders, he said, but added that the government would not offer them full pardons yet.
Khartoum is also facing an insurgency in the South Kordofan and Blue Nile areas, where the Sudan People's Liberation Movement-North has been battling its troops since 2011.
Bashir, who is wanted by the International Criminal Court for alleged war crimes in Darfur, called for the national dialogue last January but the talks have yet to start.
African Union chief mediator Thabo Mbeki met Bashir in Khartoum today and is expected to stay for one week for talks about the national dialogue.
The UN says that the conflict in Darfur alone has killed 300,000 people and forced 2.5 million to flee their homes.
Khartoum puts the death toll at 10,000.
