The Liberal Democrats are calling for Keir Starmer to start talks on joining the EU customs union as a first step towards rejoining the European Union. The party believes that a customs union deal would boost trade for British businesses and generate tax revenue for public services. Sir Ed Davey has written a letter to Chancellor Rachel Reeves urging her to commission the Office for Budget Responsibility to explore the economic impact of a new customs deal with the EU. The forecasts should be made public alongside the Spring Statement on 26 March.