However, Michel Barnier also urged the UK to show “more realism” on the degree of cooperation possible.
Speaking at the EU Fundamental Rights Agency in Vienna, he said that the “unique” and “unprecedented” cooperation on intelligence within the EU is enabled by “trust between member states.”
He added, “This trust does not fall from the sky and is founded by our common ecosystem. If you leave this ecosystem you lose these benefits. You are a third country because you have decided to be so. And you need to build a new relationship.”
Barnier also rejected the approach of the British government, which he argued wants “to maintain all the benefits from EU membership without being in the EU.”
He said, “The British try to blame us for the consequences of their choice,” and warned that the UK will lose access to Europol databases and the Schengen information system, as well as the right to participate in the European arrest warrant.
Responding to his comments, a spokesperson for the UK Department for Exiting the EU said, “Keeping citizens in the UK and EU safe is an absolute priority. We are proposing an internal security treaty to deliver this. We recognise we will be a third country, but we start from a unique position of complete alignment.”
Speaking separately, Jeremy Fleming, director of the UK surveillance agency GCHQ, said the UK had played a “critical role” in the disruption of terrorist operations in at least four European countries in the past year, adding, “those relationships, and our ability to work together, save lives. That will continue after Brexit, for the benefit of the UK and our partners across Europe.”
He was speaking on Wednesday during a visit to Nato headquarters in Brussels.
Meanwhile, UK Prime Minister Theresa May has welcomed the passing of the Brexit bill through Parliament as “a crucial step” in delivering a “smooth and orderly Brexit”.
In a vote on Wednesday, UK peers accepted the amendment to the EU Withdrawal Bill sent to them from the House of Commons, meaning the bill now goes for Royal Assent, becoming law. The vote passed 319 to 303 after would-be Tory rebel MPs were given assurances they would have a meaningful say.
May said more detail on the UK-EU’s future relationship will be given soon.