Sudan's President Omar al-Bashir has ordered his country's border with South Sudan opened for the first time since the south broke away to become an independent country in 2011.
Sudan's state-run news agency said Wednesday that the president "ordered the relevant authorities to take all measures required to implement this decision on the ground."
The move was a major step toward improving relations between the neighboring countries that have been at each other's throats since the South Sudanese seceded.
The south took much of Sudan's oil reserves but agreed to pay the north a fee to transmit the oil through its pipelines. Bashir has agreed to consider cutting those fees.
Both sides have also battled over unresolved border disputes, including control of another large oil field.
Civil war broke out in the south in 2013, sending hundreds of thousands of refugees fleeing into Sudan.
The south accused Sudan of backing anti-government rebels while Sudan alleges the south supports separate rebellions in the Darfur, and the Blue Nile and South Kordofan regions.