EU President Donald Tusk warned on Thursday his native Poland to avoid burning its bridges with the bloc after the right-wing Polish government was isolated in opposing his re-election.

"Be careful of the bridges you burn because once they are gone you can never cross them again," Tusk told a press conference at a summit of European Union leaders.

"I want to dedicate this to all member states, especially before our discussion on the future of Europe before the Rome (summit) celebration, but today especially to the Polish government."