The US is heading for a budget deficit of more than $1 trillion (£707bn) by 2020 following tax cuts and higher public spending, according to the Congressional Budget Office.

It said that while the measures will temporarily boost the US economy, they will exacerbate its long-term debt.

The agency said US debt could rise to a level comparable to World War II and the financial crisis.

It warned that it would have “serious negative consequences” for the US.

The CBO’s report has been revised to incorporate the effects of a new $1.3 trillion government spending bill and the $1.5 trillion in Republican-led tax cuts approved last year.

It lifted its economic growth forecast for this year and next to 3.3% and 2.4% respectively.

However, the non-partisan CBO said the deficit – the difference between what the government spends and what it receives through tax receipts – is expected to rise to $804bn in 2018 from $665bn in the previous year.

The budget deficit is then expected to grow to $1 trillion by 2020.