The Chancellor of the Exchequer will make a “Spring Statement” on public finances to Parliament later.
Commenting, Chuka Umunna MP, leading supporter of the Open Britain campaign, said:
"It is essential that the Chancellor uses his statement today to set out the costs of Brexit to the Exchequer.
"It is the absolute duty of Ministers to bring to Parliament all modelling and estimates that exist. The fundamental reason we have a Parliament is to stop the executive from imposing taxes and charges on the people without consent.
"This is now about our basic democratic rights. Ministers cannot continue to hide the truth from the voters and their representatives."