The Duke of Cambridge wrote to the grieving girlfriend of tragic Capitol riot police officer Brian Sicknick

The royal's letter - which breaks from royal tradition of steering clear from politics in Britain and abroad - said: "Please forgive me if I am intruding but I wanted to write and let you know how sorry I am about the death of your partner, Brian."

William added he watched the "harrowing events that took place at the Capitol" and felt compelled to hail Sicknick's "patriotism" and "selflessness".

His note went on: "By all accounts Brian performed valiantly while on duty and despite suffering injuries continued to do his utmost to protect those inside.

"I hope you can take some comfort from knowing that it is thanks to law enforcement officers like Brian that the situation did not escalate further and democracy was upheld."

It is understood to be the first time William has publicly waded into US issues, in stark contrast to his younger brother the Duke of Sussex, 37, and his wife the Duchess of Sussex, 40, known as Meghan Markle before she married Prince Harry.

William's letter was revealed by Sicknick's partner Sandra Garza on CNN on Friday. (17.06.22) She also used her appearance to slate ex-US president Donald Trump, 76, who has been accused of inciting a "coup" after his supporters stormed Congress on 6 January 2021 in a bid to thwart the certification of Joe Biden's election.

Garza fumed about not getting any sympathy statement from the ex-reality TV star: "Trump does not give two c**** about law enforcement or Brian and yet Prince William took the time to honour me and Brian."

Kensington Palace has not yet commented on the letter.

The Queen did not comment on the global political outrage sparked by the riot.

But Prince Harry claimed he battled to warn former Twitter chief ex ecutive Jack Dorsey, 45, the form was being used to plot a "staged coup".

He said last November: "Jack and I were emailing each other prior to January 6, where I warned him that his platform was allowing a coup to be staged. That email was sent the day before and then it happened, and I haven't heard from him since."

Harry added in January the riot was a "literal attack" on democracy only made possible as it was arranged by extremists on social media by extremists.