BRUSSELS -- The leaders of Germany and France led a fresh effort Friday to breathe life into long-stalled talks to normalize ties between Serbia and Kosovo more than 20 years after Belgrade sent troops into its then-province to crush a separatist uprising, but Serbia's president said the Europeans have unrealistic expectations.

French President Emmanuel Macron and German Chancellor Angela Merkel held virtual preparatory talks with Kosovo's prime minister and Serbia's president aiming to pave the way for the first face-to-face meeting of the Balkan countries' leaders since November 2018 under a European Union-backed dialogue process.

Speaking after the meeting, Serbian President Aleksandar Vucic said "we had really tough negotiations," and that he told Macron and Merkel that if Kosovo's independence "is what they want to talk about, then these talks are completely meaningless."

"We will not have an easy time in the future. I think we will be exposed to great, great, let me not say pressure, but expectations from our European partners, Vucic said. "At the same time we are faced with a completely unrealistic approach from Kosovo Albanians who want it all, leaving Serbia without anything," he said.

Ethnic Albanians made up the Kosovo Liberation Army that fought Serbian troops during a 1998-99 war and now are the majority in Kosovo, which unilaterally declared independence from Serbia in 2008.

Despite the longstanding differences between the neighbouring countries, a French presidential adviser said "the dialogue is picking up" and that Vucic and Kosovo Prime Minister Avdullah Hoti showed their goodwill simply by coming to Paris for separate meetings earlier this week.

The adviser, who is not authorized to be publicly named under presidential policy, acknowledged that the talks are complex but said that no one underestimates the challenges, and all sides understand that finding a solution is important for regional security.

"We recognize Kosovo... Serbia doesn't. That's the difficulty to resolve," said the adviser, who added: "We should not allow a vacuum to develop in this region."

EU foreign policy chief Josep Borrell, who was also involved in the meeting, is due to host more video talks with Hoti and Vucic on Sunday. EU officials hope the two will come to Brussels in person next Thursday.

Serbia has refused to recognize Kosovo as a separate country, and tensions have continued to simmer between them. The United States and the European Union have been working to help normalize ties between the two countries.

The EU-facilitated negotiations, which the Europeans say is the only forum that addresses their future aspirations, started in March 2011 and have produced some 30 agreements, but most of them have not been observed. Some EU member states themselves have not recognized Kosovo's independence.

The EU and the U.S. officially have the same goal -- resolving one of the last major standoffs in the volatile Balkans region after the 1998-1999 war and a NATO intervention to stop a bloody Serb crackdown against Kosovo Albanian separatists.

Still, Sunday's meeting comes after a U.S. effort to get the sides talking, which was not co-ordinated with the Europeans and raised eyebrows in Brussels. That effort appeared to founder when Hoti cancelled his trip to Washington after Kosovo's president, Hashim Thaci, was indicted for alleged war crimes.

European Commission spokesman Peter Stano said it is important to focus on moving things forward and not to get bogged down in the thorny issues involved in the talks.

"This is not a one-off event. Dialogue is a process," Stano told reporters. "What is important at this stage is to get things moving."