The UK National Audit Office (NAO) out with the big cost warning, higher than the £35bn-£39bn figure put forward by Theresa May
- UK could pay an extra £3bn more in budget contributions
- as well as an additional £2.9bn to the European Development Fund
- Auditors have concluded that the Treasury's estimate includes £7.2bn of receipts which will go directly to the private sector and not to the government's accounts
