South Sudan's President Salva Kiir is to make a visit to Khartoum on Saturday, his first since the south's formal secession from the north, to discuss key unresolved issues, the foreign ministry said.
Kiir is to be received at the airport by Sudan's President Omar al-Bashir with their discussions due to start later the same day, foreign ministry spokesman Al-Obeid Merwah said.
"The negotiations, which will cover the issues of mutual concern, will be fully successful and will lead to good, neighbourly, cooperative relations between the two countries," he said in a statement.
South Sudan proclaimed formal independence on July 9, at a ceremony in Juba which Bashir attended as a guest of honour.
But the two sides failed to resolve a number of thorny bilateral issues ahead of partition, some of which have since threatened to seriously undermine relations between the north and south.
These include the bitterly contested future status of the Abyei border region, which the Sudanese army occupied in May, and the division of the country's oil, most of which is produced in the south, as well as currency, border demarcation and debt.
Kiir will be accompanied by South Sudan's minister of cabinet affairs, Deng Alor, as well as the oil, finance and foreign affairs ministers.
Merwah said a joint press conference would be held on Sunday to announce the results of the negotiations.