Serbia pulled out of EU-backed peace talks on Kosovo on Wednesday after fresh unrest in a disputed border region.
The talks aim to settle a row stemming from Serbia’s refusal to recognise Kosovo’s independence.
On Tuesday six Kosovar Serb protesters were wounded in clashes near the frontier with Serbia.
Four NATO peacekeeping troops were also injured.
Progress in the peace negotiations is crucial if Serbia is to formally became a candidate for EU membership in October.
Kosovo is predominantly ethnic Albanian but its north is home to 60,000 Serbs.
They do not recognise the Pristina government and its attempts to control the border.
Tensions flared in July when Kosovo placed a trade ban on Serb exports.
Kosovo’s Prime Minister, Hashim Thaci, vowed to break up the protests in the disputed region.
“We will continue with the removal of barricades and no obstacle can stop the government exerting its authority there,” he said.
Kosovo broke away from Serbia in 2008.
Its independence has been recognised by at least 80 countries, including the United States and 22 EU members.
Emerging global players such as Brazil, Russia, India, China and South Africa have so far refused to recognise Pristina’s split from Belgrade.