This year’s deadline for submission was 18 April. The Internal Revenue Service (IRS) allows individuals and businesses to apply for a six-month extension to gain more time to file a return.

Trump's application for an extension, which does not provide more time to pay taxes, was announced by the White House spokesman Sean Spicer at the weekend.

As a candidate and as president, Trump has refused to release his tax returns, breaking a decades-long tradition. He has said he would release them when the IRS completes an audit, although both tax officials and others have said such audits are not a bar to taxpayers releasing their returns.

During his campaign Trump declined to make public his tax returns, and demand for more personal tax transparency from the President has risen following his release of plans for reforming the US tax regime and as a result of recent concerns over Trump’s possible links with Russia.

Trump’s personal lawyers have provided a letter stating that his returns from the past 10 years show that, with a few exceptions, he received no income from Russian sources and owed no debts to Russian lenders.

In an interview in May Trump told The Economist that ‘nobody cares about my tax return except for the reporters’ and that ‘don’t forget I got elected without it.’