Royal Train tour: William and Kate hope to help keep Britain's morale on track

They had carried on with online engagements even after most people had "Zoomed" out.

But in the end the Duke and Duchess of Cambridge came to the conclusion that a mini-tour of the UK might bring some Christmas cheer in the wake of the most miserable 12 months in recent memory.

The decision to take their first ever journey aboard the Royal Train came after discussions with aides about how to highlight the impact of public generosity during the Covid pandemic.

Following the huge success of Clap for Carers earlier in the crisis, both William and Kate expressed a desire to pay tribute to those who have gone "above and beyond" this year.

According to one well-placed source, lockdown has taught the couple not only the value of the Royals in times of crisis but also the importance of their power to be agents of the nation's gratitude.

"What this year has done has reinforced the value of the royal family as natural actors of state," said the insider. "They are not celebrities – they are there, effectively, to thank people on the public's behalf."

The whistle-stop trip, which starts on Sunday and will take in cities including Edinburgh, Manchester and Cardiff, comes after a year of cancelled royal events and overseas tours.

Ordinarily, the couple would have undertaken both a spring and autumn visit abroad but, like the rest of the Royals, have been "grounded" by coronavirus.

Yet having launched a number of well-received initiatives since the first lockdown began in March, they have taken it upon themselves to "keep spirits up" during the biggest national emergency in peacetime.

Kate was delighted by the response to "Hold Still", her ambitious community project to create a unique collective portrait of the UK during lockdown. People of all ages were invited to submit a photographic portrait, taken over a six-week period during May and June, and over 31,000 submissions were received from across the country, with entrants ranging from four to 75 years old.

From these, a panel of judges selected 100 portraits, which were exhibited around the UK.

Meanwhile, William decided to raise awareness of the pandemic's toll on mental health, focusing particularly on the impact on men by holding discussion sessions with footballers.

He also sent himself up in a Blackadder spoof with Stephen Fry for a BBC fundraiser – and called the numbers in a virtual game of bingo for care home residents with Kate.

The insider said the engagements were intended to "lighten the mood" at a difficult period in everyone's lives.

"They could have gone really very quiet during the pandemic and probably wouldn't have faced much criticism," the source added. "But actually they chose to keep busy. They've been itching to get back out and about, and the UK tour on the Royal Train enables them to do that in a safe, socially-distanced way."