European Parliament President David Sassoli has called for allowing the Western Balkan states into the European Union, calling enlargement a "positive project for peace and prosperity."
"Enlargement can bring immense benefits both to the region and to Europe as a whole, helping to secure a stable, prosperous and peaceful continent," he told the Funke Mediengruppe on Sunday.
The pace, he said, would depend on the Western Balkan countries' fulfilment of the accession criteria. "Reforms still need to be completed in every single one of these countries." But the European Union must also keep its promises and recognize progress, he said.
In addition to Serbia and Montenegro, the Western Balkan countries include Albania, North Macedonia, Bosnia-Herzegovina and Kosovo.
The EU is already conducting accession talks with Montenegro and Serbia, while Albania and North Macedonia are official candidates.
Bosnia-Herzegovina and Kosovo have so far been considered potential candidates for negotiations.
Vetoes and blockades
Late last year, the Czech Republic and Slovakia blocked the adoption of an important text on progress in the EU enlargement process.
Before then, Bulgaria vetoed the start of EU accession negotiations with North Macedonia over a dispute stemming from their shared history; Sofia also refuses to recognize the Macedonian language as its own entity, saying its a Bulgarian dialect.
The move also also blocks the planned start of EU accession negotiations with Albania.
The situation is considered problematic because the Balkan states are also being courted by countries such as Russia, China and Turkey.