KIEV           -     Troop withdrawals in a village in the Donbass region of eastern Ukraine will begin on Saturday at 1000 GMT, the Organization for Security and Co-operation in Europe (OSCE) said in a statement. Ukraine and Russian-backed separatist rebels have agreed to phased troop withdrawals as a confidence building measure that could pave the way for a four-way summit between Ukraine, Russia, France and Germany on the Donbass conflict.