Sudan is pursuing both military and diplomatic measures to end the South's eight-day occupation of its key Heglig oil field, but it must stop "by hook or crook," a foreign ministry official said on Wednesday.
"Military steps are underway ... and they are calculated measures," Omar Dahab, head of the ministry's crisis team, told a news conference.
"At the same time, they are taking into consideration the diplomatic and good offices efforts regarding the ending of the occupation.
"We have to end the occupation by hook or crook, by either way."
Clashes broke out last month in the Heglig area and escalated last week with waves of aerial bombardment hitting the South and Juba's seizure of Heglig on April 10.
Sudan's military has released virtually no information about the situation on the ground but said last Saturday its forces were kilometres (miles) from Heglig.
Many in Khartoum are asking how the South was able to take over the area so easily in the first place.
South Sudan's army has vowed to hold its positions in Heglig, despite air strikes.
This is the worst fighting between the two neighbours since South Sudan won independence in July after a 1983-2005 civil war which killed two million people.