Majzoub al-Khalifa, head of Sudan's delegation to the African Union-sponsored talks in Abuja, said there was "a lot of common ground for agreement".
"We are very much hoping to come to a final peace agreement in this round," he said in Khartoum on Thursday.
Al-Khalifa said the government would do its best to reach an agreement "before the end of this year so that peace in Sudan will be finalised by January in all parts of Sudan".
Khartoum and rebels from southern Sudan promised the UN Security Council in November they would reach a deal to end a separate 21-year-old civil war by 31 December.
Analysts say the Darfur crisis has slowed progress towards a southern peace deal.
SLA has accused Khartoum of
increasing attacks in Darfur
Foreign Minister Mustafa Osman Ismail said the government would also hold talks with a third group from Darfur, the National Movement for Reform and Development (NMRD).
The discussions with the group, which had no part in previous talks, would take place in the next few days and cover security and humanitarian issues, he said.
Al-Khalifa, head of the government delegation, did not rule out the third group joining the Abuja discussions.
Rebels said they would attend the talks in the Nigerian capital Abuja but accused Khartoum of launching fresh attacks in the Darfur region in western Sudan.
"This is not a serious round of talks. The government is mobilising its troops and directly attacking," Khalil Ibrahim, president of the rebel Justice and Equality Movement (JEM), said.
"This is not a serious round of talks"
The JEM also said the NMRD was not a rebel movement, simply a group of outlaws armed by Chad, and it would not accept them as negotiating partners in Abuja.
The Sudan Liberation Army, the other main Darfur rebel group, has also accused the government of increasing attacks in Darfur ahead of the talks.
The Darfur talks in Abuja adjourned in November, when the sides signed agreements on security and humanitarian issues.