Emails seen by the Mail on Sunday show Dr Tim Leunig suggested Britain could become more like Singapore, which is “rich without having its own agricultural sector”.

He also reportedly questioned tax breaks given to farmers, and suggested that the UK could import its food in future.

The comments were made in emails sent last week to the National Food Strategy, the Government's wide-ranging review of the British food system.

Dr Leunig wrote: "Food sector isn't critically important to the UK, and ag[riculture] and fish production certainly isn't."

He then went on to query tax breaks given to farmers, saying: "We know that supermarkets also make very little, and that lots of restaurants go bust.

"Not sure I buy a 'life is tough for farmers, easy for restaurateurs' approach."

After being challenged by members fo the review's advisory panel, Dr Leunig is then reported to have said: "All I am saying is that, as a logical possibility, a nation (or region) can import stuff. We see that in many places for many goods and services. Singapore imports (almost) all its food, Germany all its oil, Japan all its planes and all its oil, Australia and New Zealand import all their cars, all their planes and all their oil, while Iceland imports oil, cars, planes and graduate-level education."

The Government has distanced itself from Dr Leunig’s comments, with a spokesman saying: “We have made clear the comments are not in line with government policy.”

Sources also told the PA news agency that the remarks were made in personal emails and that Dr Leunig was not speaking in his Treasury role.

His comments come after both the UK and the EU published their negotiating mandates earlier this week, with talks set to begin in the coming days. 

Agriculture and fishing policy is set to be a sticking point in future discussions, with the EU’s Michel Barnier stating the bloc's boats must have access to UK waters.

Issues around animal welfare are also set to come up, with the EU set to insist that a ban on chlorinated chicken and hormone-fed beef imports from the US must remain in place post-Brexit.

Meanwhile farming industry leaders have called on the Government to uphold current standards to set a “benchmark” to other countries around the world.

NFU President Minette Batters told the union’s annual conference: "To sign up to a trade deal which results in opening our ports, shelves and fridges to food which would be illegal to produce here would not only be morally bankrupt… It would be the work of the insane."