It said: “It is possible that the transition period ends without any agreement on the future trading relationship.
“Even if a trade agreement between the EU and the UK is concluded, the future EU-UK trading relationship will be less beneficial than assume in the purely technical assumption of an unchanged trading relationship, and will therefore lead to more negative outcomes for both sides, in particular for the UK for which trade with the EU is more important than trade with the UK for the EU.
“A failure to secure an agreement on the future trading relationship between the UK and the EU could also result in lower growth, particularly for the UK.”
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