Sudan President Omar al-Bashir has said the disputed border region of Abyei is a source of potential conflict with newly independent South Sudan. Abyei remains part of northern Sudan and the protocols governing it must be respected, Mr Bashir told the BBC a day after South Sudan\'s independence. He spoke of his sadness over the division of his country, but said it was a price worth paying for peace. The south struggled to break away for decades at a cost of 1.5 million lives. President Bashir said he would have preferred to preserve the unity of Sudan, in an interview for the BBC\'s Hardtalk programme on the day after South Sudan gained independence. But the will of the people in the south had to be respected to avoid a return to armed conflict, he conceded. Asked about potential sources of friction in the future, Mr Bashir pointed to Abyei, a border area claimed by both north and south. map Fighting in Abyei and another border region, South Kordofan, forced some 170,000 people to flee their homes in the run-up to southern independence. Both sides agreed to withdraw their troops, leaving a 20km (12-mile) buffer zone along the border, in a deal brokered last month. The BBC\'s Peter Martell in the southern capital, Juba, says the agreement is not easy to implement, because parts of the border are still contested and have not been demarcated. In a clear warning to the south, Mr Bashir said there could be renewed hostilities if agreements on disputed areas such as Abyei were not respected. \'Ethiopian troops welcome\' He said Abyei was a part of northern Sudan and could only join the south with the approval of nomadic Arab tribes in a future referendum, which he described as an unlikely scenario. He said he wanted United Nations peacekeepers currently patrolling the region to leave. But he welcomed the prospect of their replacement by Ethiopian troops, a move endorsed by the UN Security Council earlier this week. \"The Ethiopians have a mandate to keep peace in the zone, so we welcome the Ethiopian troops. Both of us welcome them, because they are capable of doing their job, unlike the current troops who have failed to keep peace in this zone,\" the president said. \"There are some arrangements, and as of now we are talking about creating some institutions. Two presidential representatives from each side. These are the authorities which will be running Abyei, security-wise and service-wise.\" \"There\'s a protocol on Abyei - a protocol that governs Abyei if there\'s a peaceful solution. But in the past, we were forced to fight when they [the south] tried to impose a new reality.\" From BBC