UK will 'regret' leaving EU after Brexit, warns Jean-Claude Juncker

The UK will "regret" its decision to leave the European Union, Brussels' top official has warned.Things "cannot remain as they are" for the UK in its relationship with the EU once it has left the bloc, European Commission president Jean-Claude Juncker said in an address to the European Parliament.Mr Juncker was cheered by eurosceptic MEPs as he referenced the UK's departure date of March 29 2019.