South Sudan says its forces are still in the process of withdrawing from the disputed oil-rich region of Heglig.
"Our troops are still withdrawing; it will take three days," South Sudan's Information Minister Barnaba Marial Benjamin said.
Sudanese army spokesman Sawarmi Khaled Saad told AFP that the withdrawal was in response to “the request of the UN Security Council and others, as a member of the UN and the African Union”.
Tension between the two neighboring states escalated after the South seized the oil-rich town along with its oil fields last week.
The UN Security Council has discussed imposing sanctions on the African neighbors if they do not stop the violent clashes.
Heglig is internationally regarded as part of Sudan, something South Sudan disputes.
A historic peace agreement between North and South Sudan signed in 2005 paved the way for an independence referendum in January 2011, in which southerners voted almost unanimously to secede.
South Sudan became independent on July 9, 2011, after decades of conflict with the north. The new oil-rich nation is one of the least developed countries in the world, where one in seven children dies before the age of five.