The Duke of Cambridge has praised the Irish Guards for their “unwavering commitment” to their country “whenever and wherever” they are needed most.

William, Colonel of the Irish Guards, sent a letter to the Army regiment, heralding the “grit and determination” they have shown during the pandemic.

The second in line to the throne has held the honorary military post for 10 years.

William’s brother the Duke of Sussex was stripped of his own honorary military roles, including Captain General of the Royal Marines, by the Queen last month after Megxit was made permanent.

Harry had hoped to retain his posts with the Forces despite quitting royal duties for a life in the US, saying in his Oprah interview that he was hurt but respected his grandmother’s decision.

The Duke and Duchess of Sussex have left the monarchy in crisis after their bombshell televised tell-all in which they accused the royal family of racism and the institution of failing to help a suicidal Meghan.

Remembrance Sunday 2017
Harry has been stripped of his honorary military titles (Dominic Lipinski/PA)

William, a future head of the Armed Forces, focused on his military role, highlighting the Guards’ work at mobile Covid-19 testing units and their deployments overseas.

Wishing the regiment a Happy St Patrick’s Day, he added: “This monumental scale of support for the national effort, alongside the fulfilment of your other duties, has once against demonstrated your unwavering commitment to your country, whenever, and wherever, you are needed most.”

The duke, who is facing his own rift with Harry, also wrote about the love and support the Guards receive from their friends and families.

“We also know that behind each of your achievements stands the continued love and care of your friends and families; the value of the support provided by our entire Regimental Family cannot be overstated,” William said.

Meghan’s friend, the US breakfast show host Gayle King revealed on Tuesday that initial talks between Harry and his father the Prince of Wales, and William were “not productive”.

William added in his letter: “As your Colonel, I could not be more proud of the grit and determination displayed over the last 12 months”.

William and the Duchess of Cambridge traditionally attend the Guards’ St Patrick’s Day parade each year at barracks in London.

Irish Guards St Patrick’s Day parade
The Duke and Duchess of Cambridge enjoy a pint of Guinness after attending the St Patrick’s Day parade at Cavalry Barracks in Hounslow in 2019 (Gareth Fuller/PA)

The duke said: “Sadly Covid restrictions means that we cannot be with you this year, but it has been heartening to hear about the important work that you have been doing to support the response to the pandemic across the UK.”

A smaller, socially distanced parade was held for new recruits in the Infantry Training Centre (ITC) Catterick.