Fox reportedly blamed the commission's "intransigence" and "theological obsession" with EU rules.
READ MORE: Bank of England Chief Warns of 'Uncomfortably High' Risk of No-Deal Brexit
Chief EU negotiator Michel Barnier earlier this week explained in an article published by several outlets that the European Union could hardly agree to certain provisions laid out in the UK government's recent white paper on Brexit.
The European Union is wary, in particular, of the UK proposal to collect some taxes on behalf of the bloc at the UK border as part of a "facilitated customs arrangement" after the United Kingdom leaves the customs union.