The European Commission on Wednesday urged EU nations to open membership talks with Albania and North Macedonia, saying the Balkans countries "have delivered on reforms."
EU foreign policy chief Federica Mogherini told reporters that accession talks two countries "as soon as possible. They are ready. This is our assessment."
However, the expansion over the years of the 28-nation EU has complicated decision-making in the world's biggest trade bloc, and it's unclear whether member states will endorse the move. On taking up his post as commission president in 2014, Jean-Claude Juncker said no countries would join the EU during his term, which ends Oct. 31.
Mogherini said that it's not as if Albania and North Macedonia would join "the union tomorrow morning. It's a complicated process."
The prospect of EU membership has been a powerful force for reforms in the volatile Balkans since the former Yugoslavia disintegrated into war in the early 1990s.
Mogherini warned member countries that Europe is "at a crossroads. We always say that it is a merit-based process, so when merit is assessed as positive it needs to be acknowledged."
"Failure to recognize and respond to objective progress would damage the European Union's credibility," she said, adding that it could also "undermine stability and seriously discourage further reforms."
Her warning comes a day after Serbia put its troops on full alert after heavily armed Kosovo police fired tear gas and arrested about two dozen people in Serb-dominated northern Kosovo in what they called an anti-organized crime operation.
EU-backed talks between the two on normalizing relations are bogged down.