The UK must seek the “closest possible” economic relationship with the EU to minimise the damage that will be caused by Brexit, according to the Organisation for Economic Cooperation and Development.

In its biennial survey of the UK economy on Tuesday, the Paris-based organisation said there were already signs that Brexit-related uncertainty is damaging Britain’s economic performance. The OECD said a reversal of the Brexit decision — either as the result of a second referendum or at the hands of a new government — would have a “significant” positive impact on growth.

But in a press conference in London on Tuesday, Angel Gurría, secretary-general of the OECD, sought to play down the suggestion that the Brexit vote should be reversed, saying: “After the decision, regardless of what I personally and the OECD institutionally had been advocating for before the referendum, we now are devoted to?.?.?.?make the transformation and to make the deal as seamless, as smooth as possible.”