West worried over build-up of rebel reinforcements in eastern Ukraine

The US and the European Union have reportedly raised fears over a build-up of separatist reinforcements in eastern Ukraine

The EU's head of foreign policy, Federica Mogherini, said the latest reports by the OSCE [Organisation for Security and Co-operation in Europe] Special Monitoring Mission in Ukraine were "worrying," the BBC reported.

According to the report by the OSCE, convoys in separatist held areas with huge amounts of heavy weapons, tanks and troops were fast moving westwards.

US National Security Council spokeswoman Bernadette Meehan said that the West was very concerned by intensified fighting in eastern Ukraine, as well as reports that Russian backed and supplied separatists were moving large convoys of heavy weapons and tanks to the front lines of the conflict.

Kiev on Friday accused Russia of sending some 32 tanks, 16 artillery systems and 30 trucks loaded with fighters and ammunition dozens into eastern Ukraine.