Sudan will begin pulling its troops out of the disputed border region of Abyei on Tuesday, an army spokesman has said.Abyei is claimed by both Sudan and South Sudan, which broke away on 9 July 2011 after decades of civil war.The status of Abyei was left undecided in the 2005 peace deal between the two governments, and a referendum on the issue has been postponed indefinitely.Thousands of civilians fled when Sudanese forces seized the area in May last year.In talks due in the Ethiopian capital Addis Ababa on Tuesday, the two countries are expected to cover several border disputes that have caused friction, including Abyei.Sudan has decided to redeploy its troops out of Abyei in order to "offer a good environment for the talks", military spokesman Sawarmi Khaled Saad said in a statement quoted by the AFP news agency.In recent months, cross-border clashes centred on the neighbouring oil-rich region of Heglig have brought the two sides close to all-out war.