Serbian officials have met European Union mediator Robert Cooper to discuss the latest bout of ethnic tensions in northern Kosovo, the Voice of America said.

The head of Belgrade's negotiating team, Borislav Stefanović, and Serbian minister for Kosovo Goran Bogdanović met Cooper on August 1 2011 in the southern Serbian town of Raska.

Stefanović told reporters after the closed-door meeting that there would be more discussions, but he did not say when, VOA said. Serbian news media said that Cooper returned to Priština to convey Serbia's demands.

Serbian news website B92 said that it had learnt that the talks were difficult, with the participants "remaining in their positions". 

According to Belgrade-based news agency Tanjug, Bogdanović said that he expected the outcome of the talks with Cooper to be a return to the situation in northern Kosovo that existed before July 25, when the Priština government sent over police units to impose a ban on goods from Serbia on two checkpoints in the northern, Serb part of Kosovo.

Serbia's government said on August 1 that it was sending trucks with food aid for Serbs in northern Kosovo, including 30 tons of flour, 20 tons of sugar and cooking oil each and five tons of powdered milk.

The region has experienced food shortages after special forces of Kosovo's authorities a week ago seized two border crossings in Serb-dominated northern regions to enforce a ban on imports from Serbia.

Kosovo's government imposed the ban in late July in retaliation for Serbia's blocking of Kosovo's goods.