The Prince of Wales, the Duchess of Cornwall, the Duke and Duchess of Cambridge, the Princess Royal, the Countess of Wessex and Princess Alexandra took part in the tributes.

Prince Charles thanked nurses for their "diligence" and "courage".

While Camilla said: "Extraordinary times call for extraordinary people."

In a video montage released by Kensington Palace on social media, many nurses were seen wearing face masks as they spoke to the royals about the impact of Covid-19.

In one call, the Duchess of Cambridge said: "I don't know how you manage to do this and keep the show on the road despite the extra pressures you're all under and the challenging conditions - it's just shown how vital the role that nurses play across the world. You should be so proud of the work that you do."

At the beginning of the video, the Queen can be heard speaking to Prof Kathleen McCourt, president of the Commonwealth Nurses and Midwives Federation.

After being greeted by Prof McCourt with a "Good afternoon, Your Majesty", the Queen says: "This is rather an important day... because obviously they've [nurses] had a very important part to play recently."

The palace believes it could be the first time audio of a phone call made by the Queen has been released.

In a different call, the heir to the throne, Prince Charles, said: "My family and I want to join in the chorus of thank yous to nursing and midwifery staff across the country and indeed the world."

'Feeling the love'

Catherine and Sophie spoke together with nurses in India, Australia, Malawi, Cyprus, the Bahamas and Sierra Leone, as well as in the UK.

Sophie told some of them: "I hope you're feeling some of the love as well."

The pair spoke with nurses whose specialisms included maternal health, HIV, mental health, women's health and ophthalmology.

Anita Kamara, a nurse at the women's centre in Sierra Leone, said: "Having the future Queen and the countess speak to us today was really special."

The calls were organised by Nursing Now, a global campaign to raise the status and profile of nursing, of which Catherine is patron.

It comes as the head of NHS England, Sir Simon Stevens, said there had been a surge in interest in nursing as a career since the beginning of the coronavirus crisis.

Sir Simon said there had been a three-fold increase in the number of people clicking on the nursing pages of the NHS careers website, adding that any new recruits would be welcome.