Serbia's president hit out at Kosovo's new premier on Tuesday after talks in Brussels failed to make progress towards a solution to one of Europe's most intractable territorial disputes.
The Balkan neighbours were resuming decade-long negotiations mediated by the EU for the first time in almost a year, hoping to resolve differences still poisoning relations more than 20 years after they separated in war.
Serbia has refused to recognise Kosovo's unilateral declaration of independence after the province broke away in the bloody 1998-99 conflict that was ended only by a NATO bombing campaign against Serb troops.
The meeting was the first since Kosovo's left-wing reformist prime minister Albin Kurti claimed a landmark win in parliamentary elections in February, pledging to take a new tack in the talks with Serbian President Aleksandar Vučić.
And the encounter appeared to get heated as both men laid out their positions.
Vučić alleged Kurti had "demanded" Serbian recognition and refused to discuss a 2013 deal to set up ten Serb-majority "municipalities" in Kosovo that has never been implemented
-I've never attended this kind of a meeting in my life. Complete lack of responsibility- Vučić said in televised comments.
-The man (Kurti) came to ask me – when are you going to recognise independent Kosovo. I told him 'never', and he exploded.-
For his part, Kurti called the talks "constructive".
-We will take part in this process which is difficult- he told Kosovan media.
-The Serbian side talked about old proposals, we brought four new proposals which were refused by the Serbian side.-
EU envoy Miroslav Lajčak admitted: -It was not an easy meeting, but it was important that it happened. Both leaders had a very open and frank exchange on what they each want from the dialogue- he said.
Despite the tough atmosphere both sides agreed to press on with the talks and Lajcak said a new round would happen "before the end of July".
The EU and United States have been pushing both sides to resume the talks since the change of leadership in Kosovo.
The restarting of negotiations came as US President Joe Biden was just a stone's throw away, visiting European Union chiefs for a summit, but there was no meetings planned involving US officials.
The US has an outsized role in Kosovo, sometimes called the most pro-American country in the world, after leading the NATO intervention that forced out Serbia.
Kosovo has been recognised by more than 100 countries but Serbia still considers the territory as its southern province, and is supported by Russia and China.