LISBON, May 28 (Xinhua) -- Former European Commission Chief Jose Manuel Barroso said on Sunday that he was optimistic with the European Union's "future" despite the "mistake" of Brexit.

"I believe in a European Union with future," he said at during the Horasis Global Meeting in Cascais, around 30km from capital Lisbon, according to Lusa news agency. "Now more than ever we need a EU, which is an example of globalization."

Barroso admitted he was disappointed with Britain's decision to leave the EU and with the way it was managed, however "the EU existed before and it will continue, just as the UK will," he said.

Barroso, who was the European Commission chief between 2004 to 2014 and also prime minister of Portugal between 2002 and 2004, became chairman of Goldman Sachs last year.

Several EU leaders have voiced their concerns with Britain leaving the EU and have defended stiff divorce terms, with European Commission President Jean-Claude Juncker recently claiming British Prime Minister Theresa May didn't understand the complexity of the task, and EU chief negotiator for the exit, Michel Barnier pointing out that the Brexit deal had to be settled before negotiating future trade relationships. Enditem