David Davis has ruled out a separate Brexit deal for London and the City, delivering a blow to Sadiq Khan's hopes of introducing work visas for the UK capital after the country splits with the EU.

"We assess every single concern people raise and try to find the simplest and most secure answer to it," he said. "That, of course, will be different for financial services, than it will be for motor car manufacturers.

"But it won't be a separate deal, there's no separate deal -- this is about how to get the best for the entire country.

"I've used this phrase before and I will keep using it again: 'We were given a national instruction and we will interpret it in the national interest'."

The comments, made at a fringe event during the Conservative Party conference in Birmingham this evening (4 October), come after the Mayor of London revealed a team at City Hall were working on a visa plan.

"We are talking to business leaders, businesses, business representatives to see what we can do to make sure London doesn't lose out on the talent, the innovation, the partnership that has let us be the greatest city in the world," he told Sky News.

The Labour politician had reportedly approached Davis, Chancellor Philip Hammond and Foreign Secretary and predecessor Boris Johnson about the proposal.

Elsewhere, Davis branded the EU as a "ponderous" organisation, arguing that the UK's split from the economic and political bloc will "massively" increase the government's agility and ability to deal with financial threats and economic opportunities.

A Brexit is expected in 2019 after Prime Minister Theresa May said her government would trigger Article 50 – the official mechanism to split from the EU – by March 2017, followed by two years of negotiations with Brussels.

The Conservative administration will also scrap the 1972 European Communities Act (ECA), which gives direct effect to all EU law. In its place, a Great Repeal Bill will be tabled to enshrine all EU law into UK law and allow MPs to amend, scrap or build on legislation from Brussels after Brexit.