Britain would have to accept all EU rules, says Barnier
"If the UK is asking for a transitional period, it is the UK asking, not us," Barnier told a news conference.
"If the idea is that during this period, the UK will still participate in the single market... then it is quite clear that all European regulations, enforcement, financial conditions, supervision, all of that has to be maintained during the period, without any exceptions," he said.
May for the first time spelled out her request for a transition period of about two years after Brexit, during which Britain would stay in the EU's single market.
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