South Sudan's parliament speaker urged lawmakers Wednesday to mobilise the people to defend the fledgling nation in case of all-out attack by Sudan, as battle raged along their contested border.
"Khartoum might be meaning a real war... If you don't defend yourself you will be finished, so you should go and mobilise the people on (the) ground to be ready," Speaker James Wani Igga told parliament.
"It is an ugly development at the border, we have to be vigilant to all the points as they are attacking us in all corners," Igga said, a deputy chairman of the South's ruling party.
"In the meantime wherever you are you are to defend yourself," he added, to loud applause by politicians in the national assembly.
Fierce fighting continued Wednesday as Sudanese warplanes bombed contested regions on the border with South Sudan, the second day of violence in the oil-rich region.
South Sudanese troops held positions in the disputed Heglig oil field, seized on Tuesday from Khartoum's troops.
In Khartoum, Sudan's parliament on Wednesday called a halt to African Union-led negotiations with Juba over their protracted dispute over oil, border demarcation, contested areas and citizenship issues.
"Parliament decided to stop negotiations and withdraw the delegation immediately," state Radio Omdurman reported.
The clashes follow border fighting that erupted last month between the neighbours, the most serious unrest since Juba's independence last July, and which prompted international fears of a return to all-out war.
On Tuesday, an AFP correspondent on the South Sudanese frontline heard heavy artillery shelling and multiple airstrikes for around an hour, with one bomb dropped by aircraft landing less than a kilometre away.
Large South Sudanese troops movements were seen close to the frontier, with convoys heading up to the frontline near Heglig, an area Juba claims but which makes up a key part of Khartoum's oil production.