European Commission President Jean-Claude Juncker addresses a news conference at the EU Commission headquarters in Brussels, Belgium February 14, 2018. REUTERS/Francois Lenoir

MUNICH (Reuters) - European Commission chief Jean-Claude Juncker on Saturday underscored the importance of offering countries in the West Balkans the prospect of EU membership, but insisted they must resolve all border disputes before joining the bloc.

“There are many border disputes in the West Balkans and they must be resolved before we can go a step further,” Juncker told the annual Munich Security Conference.

He said he was frustrated by an ongoing border dispute between Croatia and Slovenia that had not been addressed before they joined the EU, and wanted to prevent a recurrence with other potential EU member states.