Donald Trump’s proposed tax plan could increase the national deficit, his Vice President Mike Pence has admitted.

Mr Pence admitted that the US could go into the red "in the short term", adding that if they could not get the economy growing at a rate of 3 per cent "we are never going to meet the obligations that we've made today."

The White House has released a one-page outline of their tax plan, which includes proposals to cut the business tax rate to 15 per cent, eliminate the estate tax and the alternative minimum tax, and reduce the number of tax brackets from seven to three. It will give cut taxes for America’s highest earners by almost 5 per cent.

Treasury Secretary Steve Mnuchin hailed the plan as “the biggest tax cut and the largest tax reform in the history of our country.”

But economists across the political spectrum have questioned its viability.

“We’ve only done the rough numbers, but this looks like a tax cut of a magnitude of about $5 trillion (£3.9 trillion),” Maya MacGuineas, president of the Committee for a Responsible Federal Budget, told The New York Times.

The conservative-leaning Tax Foundation estimates the bracket reduction and business tax cut alone would cost the Treasury up to $6 trillion (£4.6 trillion) over the next 10 years.

10 of the biggest tax havens in the world Show all 10 1 /10 10 of the biggest tax havens in the world 10 of the biggest tax havens in the world Luxembourg There are an estimated £2.5 trillion shares of mutual funds registered in the Grand Duchy, £1 trillion of which cannot be traced to an owner 10 of the biggest tax havens in the world Cayman Islands The Cayman Islands contain 6% of the world's total banking assets, but just 0.000008% of its population 10 of the biggest tax havens in the world Isle of Man David Cameron has said the Isle of Man, where there is no corporation, capital gains or inheritance tax, should not be considered a tax haven 10 of the biggest tax havens in the world Jersey There are over £3.5 billion assets per square mile on the self-governing Channel Island 10 of the biggest tax havens in the world Ireland Ireland made headlines last year when it emerged Apple was registered in the country in order to dodge over £40bn in taxes 10 of the biggest tax havens in the world Mauritius The Mauritian government notionally charges corporation tax, but companies can easily make this back through generous tax credits for foreign businesses 10 of the biggest tax havens in the world Bermuda Google holds more than £30bn in offshore cash reserves, primarily via Bermuda 10 of the biggest tax havens in the world Monaco A popular domicile for super-rich private individuals, Monaco has the most expensive property in the world. £1 million will buy just 225 square feet 10 of the biggest tax havens in the world Switzerland Switzerland has such secretive banking laws that it took until the 1990s to secure the release of Nazi cash reserves 10 of the biggest tax havens in the world Bahamas David Cameron's father ran an offshore fund which hired Bahamas residents to complete paperwork, thus dodging British tax bills

But Mr Pence told NBC News that any increase in the deficit would be made up for by economic growth.

“We’re going to lower the tax rate to three marginal rates for every American and unleash the bound up energy of the American economy,” he said.

But former Clinton administration budget director Leon Panetta told MSNBC that expecting the tax cuts to pay for themselves through growth is akin to “operating in fairyland.”

Conservative economist Douglas Holtz-Eakin agreed.

“I want a plan that’s focused on growth as much as anyone,” Mr Holtz-Eakin, president of the conservative American Action Forum, told The New York Times. “But these tax cuts are not going to pay for themselves. If you believe that, you’re kidding yourself.”

Mr Trump promised during his presidential campaign that he would grow the American economy by four per cent. But under his leadership, it has turned in its weakest first quarter in three years.