In a new memoir, Trump’s then campaign manager, Paul Manafort, writes: “On his own initiative, Trump did apologise for saying some of the things he said about Cruz, which was unusual for Trump.”

The telling vignette – possibly an embarrassing one for two powerful Republicans who have since formed an alliance of convenience – is contained in Political Prisoner: Persecuted, Prosecuted, but Not Silenced, which will be published in the US next month. The Guardian obtained a copy…

Manafort’s description of a Trump apology for such slurs may come as a surprise to both men.

Trump is famous for never apologising, whether in his business career or in his seven-year careen across the US political scene.

And when Cruz eventually came onside with Trump, in September 2016, he said: “Neither he nor his campaign has ever taken back a word they said about my wife and my family.”