Serbian President Boris Tadic is calling on Serbs to abandon roadblocks in the north of Kosovo, saying it is damaging the country's bid for European Union membership.
The appeal came as another standoff arose on Tuesday, as NATO forces tried to prevent Serb protesters from erecting a new barricade.
NATO commanders said Tuesday they will use lethal force, if necessary, to protect troops in Kosovo's tense northern region.
Meanwhile, Tadic urged NATO peacekeepers to stop using force to remove the roadblocks.
Thirty NATO soldiers and several Serbs were injured in clashes on Monday in the town of Jagnjenica. Peacekeeping forces were breaking down the the barricades and dispersing protesters with rubber bullets, water cannons and tear gas when the Serbs opened fire on the soldiers.
Serbs in the Kosovo-Serbia border region have been setting up the roadblocks since July when Kosovo's ethnic Albanian government tried to take control of the areas under de-facto Serb rule.
European Union officials have said Serbia must find a resolution to the impasse if it wants to move its bid for EU membership forward.
The violence comes as officials from Serbia and Kosovo prepare to meet in Brussels on Wednesday for EU-brokered peace talks.
Tadic has repeatedly called for an urgent stop to clashes between NATO peacekeepers and Serbs. He said the situation needs to be promptly settled through talks and without violence.
The Serbs' blockades are cutting off NATO access to a military base in northern Kosovo. NATO is demanding freedom of movement throughout all of Kosovo.
The ethnic Serbs refuse to recognize Kosovo's independence, declared in 2008.
Some information for this report was provided by AP and AFP.