New Brexit Secretary David Davis indicated shortly before his appointment that the start of formal negotiations to leave the EU should be triggered by the start of next year, with final withdrawal taking place around December 2018.

Mr Davis said that Britain should take a "brisk but measured" approach to initiating the two-year process of thrashing out a new relationship with Brussels under Article 50 of the Lisbon Treaty.

Before the Article is invoked, "serious consultation" must take place with the devolved administrations in Scotland, Wales and Northern Ireland, as well as stakeholders in the City, business organisations, the TUC, the National Farmers Union, universities and research foundations, he said.

"None of them should have any sort of veto, but we should try to accommodate their concerns so long as it does not compromise the main aim," wrote Mr Davis. "This whole process should be completed to allow triggering of Article 50 before or by the beginning of next year."

In the article published on the ConservativeHome website on July 11, Mr Davis said the ideal - and most likely - outcome of Article 50 negotiations would give the UK continued tariff-free access to the European single market while allowing it to impose new controls on migration.

"Once the European nations realise that we are not going to budge on control of our borders, they will want to talk, in their own interest," he said. "There may be some complexities about rules of origin and narrowly-based regulatory compliance for exports into the EU, but that is all manageable."

If EU nations sought to impose "irrational" tariffs on UK exports, Britain could respond by using cash raised from levies on European imports to offer financial support to affected industries, he suggested.

"Such a package would naturally be designed to favour British consumers and British industry," said Mr Davis. "Which of course is another reason that the EU will not force this outcome, particularly if we publicise it heavily in a pre-negotiation White Paper."

Mr Davis predicted that Brexit will deliver a "more dynamic" economy, striking swift bilateral trade deals with countries around the world, resulting in lower prices in the shops, higher wages for the lowest-paid and controlled immigration.

A "high-intensity" drive to negotiate free trade deals with the world's biggest economies could allow the public to see some of the economic benefits of Brexit before the likely date for withdrawal from the EU around the end of 2018, he said.