Sudan told U.N. chief Ban Ki-moon on Saturday that it had no choice but to fight back against “aggression” from South Sudan, which seized the north’s most important oil field this week.
Foreign Minister Ali Karti made the remarks when Ban telephoned him Saturday evening, the foreign ministry said in a statement.
Ban asked Sudan to show restraint, the ministry said, but Karti replied that Sudan could not wait and had acted militarily “to push out the aggressor from its land.”
The South Sudanese army claimed Saturday to still be in control of the Heglig oil center, along the disputed border, after Khartoum said it had launched an offensive to recapture the area which Southern troops took control of on Tuesday.
World powers have urged restraint after the latest round of heavy fighting began with waves of aerial bombardment against the South.
The leaders of both countries have accused each other of wanting war.
On Saturday a Sudanese air strike on Bentiu, capital of South Sudan’s oil-rich border state of Unity, left five people dead and six others wounded, state government spokesman Gideon Gatfan said.
The U.N. Security Council on Thursday demanded a “complete, immediate and unconditional end to all fighting... aerial bombardments... cross-border violence.”
It also urged the Sudan People’s Liberation Army of South Sudan to withdraw from Heglig and called on the two countries' leaders to meet “immediately,” after April 3 talks were canceled.
The clashes are the worst since South Sudan won independence in July after one of Africa’s longest civil wars, and have raised fears of a return to full-scale conflict.
Earlier, South Sudan said it had repulsed an attempt by the Sudanese army to retake Heglig.
South Sudan seized the Heglig oilfield near the border on Tuesday, prompting widespread condemnation. The African Union denounced the occupation as illegal and urged the two sides to avert a “disastrous” war.
The Sudanese army said late on Friday its forces were advancing on Heglig town, an area vital to Sudan’s economy because it has a field accounting for about half of its 115,000 barrel a day oil output. The fighting has stopped crude production there, officials say.
“Now we are moving towards Heglig town” and are “close,” army spokesman Sawarmi Khaled Saad said in a statement
“They tried to attack our positions around 40 miles north of Heglig last night but it was contained,” South Sudanese Information Minister Barnaba Marial Benjamin told Reuters.
“Heglig is (still) under our control,” he said.
South Sudan has said it will withdraw from Heglig only if the United Nations deploys forces to monitor a ceasefire.
The south seceded from Sudan last year but the two sides have not resolved issues including the position of the border, the division of the national debt and the status of citizens in each other’s territory.
Southern President Salva Kiir and his Khartoum counterpart, Omar al-Bashir, have accused each other of seeking war, prompting a U.N. Security Council call for an immediate ceasefire.
Sudan had vowed to react with “all means” against a three-pronged attack it said was launched by South Sudanese forces.
The clashes, the worst since South Sudan won independence in July after one of Africa’s longest civil wars, have brought the two former foes the closest yet to a return to outright war.
Neither army has provided casualty figures but one Southern soldier in Bentiu said earlier: “There are so many bodies at the front line, so many dead” that it is impossible to bury them or bring them back.
Much of the 1,800 km (1,200 mile) border is disputed between the neighbors, which are also in dispute over payments for southern oil passing through Sudan, the lifeline of both economies.
Landlocked South Sudan took three quarters of the former Sudan’s oil production when it seceded, but shut down in January its entire output of 350,000 barrels a day after failing to agree how much it should pay to export its crude through Sudan.
Despite international calls, Juba has refused to withdraw from Heglig unless certain conditions are met, including Khartoum’s pullout from the neighboring Abyei region it holds and which, like Heglig, is claimed by both sides.
International arbitrators ruled three years ago that Heglig was not part of Abyei, a decision the South agreed with although it does not concede that Heglig is therefore northern.
Kiir, in a speech to parliament on Thursday, said Bashir had “announced a total war with the Republic of South Sudan.”
And Bashir said South Sudan had “chosen the path of war, implementing plans dictated by foreign parties who supported them during the civil war.”
Parliaments in the two nations have called on citizens to take up defenses in case of war.