Sudan and Chad have renewed a pledge to stop hosting rebel groups hostile to each other's government, in an effort to reduce tensions.
Chad's minister of territorial administration Gen. Mahamat Ali Abdallah Nassour and Sudan's foreign minister Lam Akol Ajaween signed the agreement Wednesday in Chad's capital, N'Djamena.
The deal calls for a joint military commission to monitor the countries' shared border. It also revives an agreement reached in February, in which both sides agreed to ban rebels from establishing bases on their territory.
Despite February's agreement, each side has continued to accuse the other of creating instability.
In April, Chadian President Idriss Deby cut diplomatic relations with Khartoum after an unsuccessful rebel attack on N'Djamena.
Sudan has accused Chad of supporting rebels fighting Sudanese government forces in Darfur.
The new agreement leaves any decision on renewing diplomatic ties up to Mr. Deby and Sudan's President Omar al-Bashir.
Some information for this report was provided by AP and Reuters.