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Karel De Gucht said, in no uncertain terms, Brussels would not allow Theresa May to sign any global trade agreements if the UK maintains “access” to the bloc’s single market. Speaking to BBC Radio 4’s Today Programme, Mr De Gucht, European Commissioner for Trade between 2010 and 2014, claimed British politicians are fanciful if they believe they can agree to international trade deals as well as having access to the EU single market. The Belgian politician, who is also a close ally of arch federalist Guy Verhofstadt, when asked about a potential US-UK trade deal, said: “It is a fantasy – access to the internal market means you are a member of the internal market. “You will have to live up to the rules of the internal market, and you cannot strike trade deals with any other party.”

GETTY A potential US-UK trade deal could be blocked by European Union leaders

Access to the internal market means you a member of the internal market Karel De Gucht

Mr De Gucht added: “By the way, why would you do it? One of the advantages of belonging to the internal market would precisely be that you benefit further from the existing trade deals. “It would be complete madness if you were to do that.” The trade expert said it would be “difficult to prejudge” any potential charges enforced on Britain if it was to quit the single market and attempt to arrange an entirely separate trade deal with Brussels.

However, Mr De Gucht hinted any of the 27 remaining EU member states could block any trade talks if they feel Britain were being given a favourable deal, which helps them compete against the bloc’s members. “Why would it not be possible? But it won’t be easy,” he said. “I personally think it will be in our mutual interest to have a good trade deal, but I’m quite sure, for example, the European Union or the remaining member states will say we are not going to enter into a trade deal that is giving all kind of possibilities to Great Britain to compete from the outside.”

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