The prime minister has joined a nationwide applause to pay tribute to NHS staff on the 72nd anniversary of the health service.
The round of clapping was inspired by the weekly Clap for Carers initiative to thank key workers during the height of the coronavirus pandemic.
Prince Charles paid tribute to staff working through "the most testing time in the service's history".
It is hoped the anniversary applause will become an annual tradition.
On Saturday, UK landmarks were lit up blue in celebration and remembrance.
Downing Street, the Royal Albert Hall, Blackpool Tower, the Shard and the Wembley Arch were all illuminated and a minute's silence was held to remember those who have died during the pandemic.
The latest government figures, released on Sunday, showed a further 22 people had died in the UK after testing positive for coronavirus, bringing the death toll to 44,220.
People were also asked to place lights their windows in a show of remembrance on Saturday night, with the Archbishop of Canterbury, the Most Reverend Justin Welby, lighting a candle in Canterbury Cathedral.
Image copyright Getty Images Image caption Leeds General Infirmary workers joined in to mark the health service's 72nd anniversary Image copyright Kirsty O'Connor/PA Wire Image caption Members of the public came together - at a safe distance - to share the momentA World War Two Spitfire plane with the words "Thank U NHS" painted on its underside tipped its wings above hospitals and the homes of fundraisers and volunteers, recognising the way people have supported the NHS and local communities during the pandemic.
The National Health Service was launched on 5 July 1948, with the core principle that it is free at the point of delivery and is based on clinical need.
The idea for Sunday's round of applause was inspired by the success of the weekly Clap for Carers which saw households across the country show their appreciation for the NHS and other key workers during the lockdown.
Image copyright Getty Images Image caption Earlier, Liverpool FC players applauded key workers ahead of their Premier League match against Aston Villa Image copyright Getty Images Image caption Key workers at the Chelsea and Westminster Hospital also took part in the nationwide applauseAnnemarie Plas, who founded the Clap for Carers initiative, joined Prime Minister Boris Johnson outside No 10 for the clap at 17:00 BST.
Speaking on BBC Breakfast earlier, she said: "We have had this first part of the crisis, we don't know what lies ahead, so if we can have this one moment where we say thank you to each other and recharge our batteries for what may be a heavier time that lies ahead, then I think that is a beautiful moment."
She said the NHS helped her when she arrived in the UK from the Netherlands as a new mother, "so I feel very happy to be in touch with the NHS this way".
Image copyright Kirsty O'Connor/PA Wire Image caption Two dogs outside Chelsea and Westminster hospital were dressed for the occasion Image copyright Getty Images Image caption Sunday's applause was inspired by the weekly Clap for Carers which took place at the height of the coronavirus lockdown Image copyright PA Media Image caption The Shard in London was one of the many landmarks lit up blue on SaturdayOn Friday, Mr Johnson urged the public to applaud for "those who have worked tirelessly and selflessly to help the nation get through this pandemic".
The moment was broadcast on BBC One.
'Silver lining'
In a video message to mark the occasion, Prince Charles spoke of his gratitude and pride for the "costly sacrifices" of NHS staff.
"Despite all that has been endured, there is deep cause for gratitude, and a true reason for pride," he said.
The prince also said the pandemic had brought out the best in people, adding: "This renewal of our community spirit has been a silver lining during this dark time."
Image copyright Getty Images Image caption Annemarie Plas, pictured participating in her final weekly Clap for Carers, said earlier that the anniversary clap would be "beautiful" Image copyright AFP Image caption 10 Downing Street was lit up blue on SaturdaySpeaking at a rally celebrating seven decades of the health service, Labour leader Sir Keir Starmer said NHS staff needed a pay rise in the wake of the pandemic.
"It's very important that we don't just say thanks, but recognise in a meaningful way what the NHS has done," he said.
His comments come after unions representing more than 1.3 million nurses, cleaners, physiotherapists, healthcare assistants, dieticians, radiographers, porters, midwives, paramedics and other NHS employees wrote to the chancellor and the prime minister calling for pay talks to start soon.
Meanwhile, about 100 protesters gathered at Marble Arch in London, calling for the end of racial disparity in the health system.
Image copyright JUSTIN TALLIS/Getty Images Image caption Protesters gathered at Marble Arch before moving to Downing StreetOne of the organisers, Tyrek Morris, 21, told the crowd: "We are protesting for black lives and one of the demands we have is to abolish the racial disparity within the NHS, especially towards black women.
"We need to implement extensive measures to prevent the disproportionate suffering of black women in healthcare and bring to an end the significantly increased black maternal mortality rate."
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