LISBON, Portugal (AP) — EU Brexit negotiator Michel Barnier says talks on a free trade deal with the U.K. once the country has left the bloc might be as tough as the Brexit talks over the past years.

Barnier told the Web Summit in Lisbon that already by next summer it will be clear if the transition period put in place to agree on future relations between Britain and the bloc will have to be extended beyond the end of next year.

There are fears that Britain will transform itself into a low-regulation economy that would undercut stringent EU social, environmental and other standards.

Barnier warned that "the UK should not think that zero tariffs, zero quotas will be enough. The EU will insist on zero tariffs, zero quotas and zero dumping."

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