The public health system is the "beating heart" of the United Kingdom, according to its prime minister, Boris Johnson.

In a televised address following his release from hospital from COVID-19, the Conservative politician also called the National Health Service "the best of the country".

"It is unconquerable," Johnson declared. "It is powered by love."

He praised his doctors, some of whom were named Nick, before rattling off the names of several nurses whose "astonishing" care helped him survive.

"I'm going to forget some names, so please forgive me, but I want to thank Po Ling and Shannon and Emily and Angel and Connie and Becky and Rachael and Nicky and Ann," Johnson said. "And I hope they won't mind if I mention in particular two nurses who stood by my bedside for 48 hours when things could have gone either way.

"They are Jenny from New Zealand, Invercargill on the South Island to be exact, and Luis from Portugal, near Porto," he continued. "And the reason in the end my body did start to get enough oxygen was for every second of the night, they were watching and they were thinking and they were caring and making the interventions I needed."

In addition, Johnson thanked the British people for their efforts and sacrifices in practising social distancing, even when the sun is shining and the outdoors is so inviting. 

"We are making progress in this national battle because the British public formed a human shield around this country's greatest national asset, our National Health Service," he said. "We understood and we decided that if together we could keep our NHS safe, if we could stop our NHS from being overwhelmed, then we could not be beaten and this country would rise together and overcome this challenge, as we have overcome so many challenges in the past.

"In the last seven days, I have, of course, see the pressure that the NHS is under. I have seen the personal courage not just of the doctors and the nurses but of everyone—the cleaners, the cooks, the health-care workers of every description—physios, radioigraphers pharmacists, who have kept coming to work, kept putting themselves in harm's way, kept risking this deadly virus."