Letters have gone out to 65,000 retired NHS workers in England and Wales asking them if they would return to help out with the coronavirus crisis.
Senior officials say the ex-employees are needed to boost frontline services.
Plans have been made for them to be able to come "straight back in" to work in hospitals.
Lorry loads of protective equipment are also being shipped out to every hospital across the UK for staff.
The government has pledged to ensure that all hospitals have enough protective gear and ventilators.
Welsh Government guidance for retired health professionals on returning to work has also been published.
It includes details of what they’ll be paid and assurances that pensions won’t be affected.
They will also be given six months notice when things start to get back to normal.
The Welsh Government says: "As a fully-qualified and experienced health and social care professional who has either temporarily or permanently left health and social care, your colleagues and local community are in urgent need of your support to join the fight.
"This isn’t only about clinically treating patients – there is also a need to provide a calm and stoic presence whose ripple effect is felt way beyond any health or social care setting. "
Health Secretary Matt Hancock said that 150 lorries went out on Thursday night to hospitals and that by the end of the weekend the first batch of equipment will have gone out to all hospitals.
He said : "I totally understand you need the right protective equipment and we will do everything in our power to get it to staff."
Asked on the BBC's Breakfast programme when workers could return to the NHS, Mr Hancock said: "Well, over the next couple of weeks because for some they'll have very recently left and they can come straight back in, their annual training's been up-to-date and they can just restart.
"Imagine if you've left at Christmas, for instance, you can restart straight away. For others who have been out for a little bit longer, they may need more of a refresher because, of course, it's vital that we keep people safe, that's the whole point of the NHS.
"So the letter will go out today, we'll then be engaging individually with all those who respond and I very much hope that many, many thousands will respond.
"From those I've talked to, I think people can see just how important this is. The training will happen for those who need it over the next couple of weeks, at the same time we'll allocate people to a hospital near them because there's a logistical exercise here as well."
Mr Hancock also suggested that tougher measures could have to be brought in if people do not follow the Government's advice.
He said: "What I can say is that if people follow the advice, stay home which saves lives and if they keep apart from others, more than two metres, more than six foot, then we can tackle this and we can turn the tide.
"The scientists advise that we can turn the tide in 12 weeks if people follow the advice. If people don't follow the advice, then it'll be longer and we might have to bring more and tougher measures."
He added: "We have brought these measures in earlier than Italy did in terms of where they're up to with the number of cases.
"But we're absolutely clear that if we need to, we have the powers, in fact we've got a Bill in front of Parliament now to strengthen those powers further.
"But I think it's far better if people follow the advice."
Mr Hancock said the Government is looking "very, very closely" at why there is a coronavirus hotspot in the Midlands.
Asked on Sky News about 28 deaths recorded in the West Midlands, Mr Hancock said: "There is a hotspot, not as big as in London, but there is a hotspot in the Midlands.
"It's something that we're looking at very, very closely to find out why, frankly.
"I mean, the spread of a disease like this does tend to be in areas of hotspot and then broadening out from them.
"What we've got to do ... is to respond as well as possible."
