A choir of doctors and nurses gathered outside Great Ormond Street Hospital to lend its support to striking junior doctors.
Waving banners, the ensemble braved the cold to support doctors who formed the picket line shortly after 8am.
Wearing T-shirts emblazoned with "Support junior doctors", the group gathered at the main entrance of the hospital in central London, some wearing stethoscopes around their necks.
The choir, named the National Health Singers, was co-founded by Georgina Wood, who is a junior doctor herself.
She said: "We founded the choir in light of the position we have been put in. So the words of our song reflect how we feel about the state of the NHS but it needs to survive and hopefully we can help to do that.
"The proposed contract for us stands to put that in a position of jeopardy. That is something that none of us can stand for.
"Today is a position that junior doctors have been forced into after many months of anguish. This is the first time that doctors have gone on strike in 40 years, and that reflects the crisis that we've met."
Referring to the Lewisham and Greenwich NHS Choir, which recently claimed the Christmas number one, Dr Wood, 29, said: "The chart success has been more than we could ever bargain for, but that just reflects the way that the public support us."
The words on their banners read: "The NHS needs saving and they're not listening but we've got something to say. You can save us, don't let them break us. We are your doctors, let's keep it that way.
"The NHS should be yours, let's keep it yours. Your lives are what we stand for. So let's keep it yours."
Nadia Masood, 34, who organised the picket at Great Ormond Street, said she had been a junior doctor for 11 years, so the strike is not about her personal gain but is about anyone who has anything to do with the NHS.
"It is a public service, and we want to keep it safe," she said.
"We really want the Government to finally realise and acknowledge and properly address just how serious our concerns are. 98% of junior doctors voted for strike action and this is the first strike in 40 years.
"This isn't the first time we have been mistreated by the Government though - that just tells you how bad these changes are.
"We want them to promise us in writing, in public, that they are actually going to address the concerns that we have. And so far, they haven't. They've given us pretend negotiations."
Referring to the announcement that Tube drivers are also set to stage a round of strike action, Dr Masood said: "The Government needs to learn to negotiate with its public sector workers properly. This shouldn't keep happening."
Responding to criticism that the strike action is irresponsible, she said her mother is currently in hospital and she would not be striking if she believed it was unsafe.
"I, and all the doctors that are striking, genuinely believe that this contract is more unsafe than this strike could ever have the potential to be."
As the doctors formed their picket line, taxi drivers beeped their horns while driving past, and a nurse was seen handing out boxes of biscuits to the protesters.
The doctors' BMA placards read: "We are one profession. We stand together."
A hand-made sign read: "Junior doctors' contract not safe for patients, not fair to doctors, not right for the NHS."