Mr Trump has made tax reform one of his priorities, campaigning on a promise to simplify America’s byzantine system.

A previous plan he floated reduced the number of tax brackets from seven to three, and reduced the top tax rate to 35 per cent.

A 44 per cent level, however, is close to that proposed by Mr Trump’s presidential rival, Hillary Clinton.

It is something Mr Trump could well be considering.

“I have wealthy friends that say to me, ‘I don’t mind paying more tax,’” he said on Tuesday, in an interview with The Wall Street Journal.

“The truth is the people I care most about are the middle-income people in this country who have gotten screwed. And if there’s upward revision it’s going to be on high-income people.”