South Sudan says to quit border zone, seeks end to clashes JUBA (Reuters) - South Sudan has told the United Nations it will pull all police out of a disputed region bordering Sudan and is committed to halting all fighting with its northern neighbor, but Khartoum declared a state of emergency in some border areas. The conflicting developments on Sunday raised questions whether United Nations appeals for an end to more than three weeks of border clashes between Sudan and South Sudan would bear fruit and avert full-blown war in an oil-producing region. South Sudan, which gained independence from Sudan nine months ago under a 2005 settlement, informed the United Nations that it planned to withdraw all police from the Abyei region, according to a letter from Juba's mission to the world body. The letter, dated April 28 and seen by Reuters on Sunday, also said South Sudan was committed to an "immediate cessation of all hostilities" - after the African Union ordered both parties to stop fighting. The decision to withdraw from Abyei was taken at a cabinet meeting chaired by President Salva Kiir on Saturday. "All of these acts of peace are being done to reaffirm and demonstrate with concrete measures my government's true commitment to finding a peaceful solution to the outstanding matters with the Republic of Sudan," said the letter. But in Khartoum, Sudanese President Omar Hassan al-Bashir declared a state of emergency in some areas of South Kordofan, White Nile and Sinnar provinces bordering South Sudan, a state-linked media website said. It gave no further details. The United Nations has urged Sudan and South Sudan to withdraw troops and police from disputed regions along their 1,800 km (1,100 mile) frontier in northeast Africa. The conflict, which escalated after the two failed to agree on a string of disputes, has halted nearly all oil production in both countries, damaging their shaky economies. South Sudan's army seized the contested Heglig oilfield earlier this month but announced a withdrawal more than a week ago, bowing to U.N. pressure. Both countries claim Abyei, a border region of fertile grazing land. Khartoum took it over last year after a South Sudanese attack on an army convoy, triggering the exodus of tens of thousands of civilians. South Sudan seceded from Sudan in July, six months after a referendum agreed under a 2005 peace deal that ended two decades of civil war which killed more than 2 million people. A similar vote was originally planned for Abyei, but was never held as both sides have not been able to agree on who can participate. There are 3,800 U.N. peacekeepers in Abyei after the Security Council authorized the deployment in June last year. On Saturday, Sudan said it had arrested a Briton, a Norwegian and a South African, accusing them of illegally entering Heglig to spy for its adversary South Sudan. South Sudanese officials denied the allegations and said the men were working with the United Nations and aid groups clearing mines and had got lost in the remote territory. Additional reporting by Ulf Laessing in Khartoum; Writing by Mark Heinrich; Editing by Jon Boyle