Pensioners arriving to be vaccinated at London's ExCel Centre today complained they had been left 'breathless' by tackling 'gruelling' ramps and queuing for 20 minutes in bitterly cold temperatures.

Patients were forced to climb banks of stairs or negotiate their way up steep ramps to reach the entrance of the vaccination centre. One man had to call for a wheelchair having negotiated the first of the two ramps.

NHS sources said 400 senior citizens and key workers were vaccinated against Covid-19 at the ExCel Centre today, on its first day of operation.

They advised that numbers were likely to increase massively over the next few days. Numbers were kept to a manageable figure today, to test how the centre will run over the coming weeks.

Retired painter and decorator Ron Heath, 85, from Leytonstone, managed to make it halfway up the ramps with the help of his wife Anne and daughter Michelle.

But Mr Heath, who was having the vaccination with his wife at noon, got into difficulties half way up.

He then had to endure a 20 minute wait in plummeting temperatures as security officials from the centre went to find a wheelchair for him to allow him to complete the rest of the journey.

Asked how old he was as he sat in a chair on the ramp, he said: 'I'm 85, but it looks like I'll be 86 by the time I get out of here!'

Mrs Heath added: 'We don't want to complain or make a big deal of this, but it will be good for people to know when they come here that access is very difficult.

'I should've asked really about access, because he has a wheelchair at home and I could have brought it with us. But we are just relieved overall to be getting the vaccination.

'My husband hasn't been out of the house since March and we've had our first new great grandchild and seen the child just once. We haven't seen our grandchildren since August. We hope this will help change things and in the better for us.'

After the 20 minute wait, officials produced a wheelchair and helped his family to wheel Mr Heath the remaining few minutes to the vaccination entrance.

Another elderly man from Woodford was pushed up the ramp in his wheelchair, while his wife struggled up the ramp a minute behind with the aid of a walking stick.

Retired shop worker Bill Stansale, 82, said he found the ramps 'a bit gruelling' as he kept his vaccine appointment.

Mr William Eels, 88, of Chingford, battled to catch his breath after making his way up the ramps with his wife June.

With parking restrictions heavily enforced and only NHS workers given spaces in the car park opposite, the pensioners mostly arrived by cabs which dropped them off at the bottom of the ramps and stairs.

More than 2.4 million people in the UK have received a Covid-19 vaccine, vaccine deployment minister Nadhim Zahawi announced today, after the Government dramatically scaled up the programme.

Seven major vaccine centres opened today in the hope of inoculating the 13million most vulnerable residents by mid-February and easing the endless cycle of restrictions. Prime Minister Boris Johnson pledged to hit 200,000 jabs per day by Friday.

But the sluggish scheme has been hit by hiccups since it began last month. And it was revealed today that one hospital in London has had to bin doses of vaccines because people aren't turning up for their appointments, with staff reportedly phoning friends and family to rush in and use up leftover supplies, which only last for hours out of the freezer.

Meanwhile IT problems – known to be the health service's Achilles heel – have led to patients having to queue outside for their vaccines while staff try to get systems working. The British Medical Association (BMA) said the programme being used to organise the jab schedules was running 'unbelievably slowly' and crashing.

Seven huge mass vaccination centres opened today, in Newcastle, Manchester, Birmingham, Stevenage, Bristol, Surrey and Newham in central London.

There are at least another 1,000 sites across Britain giving out jabs made by Pfizer and AstraZeneca. Regulators last week approved a third vaccine, made by US firm Moderna, but No10 will not get any doses until the spring at the earliest.

One nurse at a West London hospital, who spoke on the condition she remained anonymous, said her colleagues were having to bin supplies of the vaccines.

Pfizer's vaccine in particular must kept in tightly controlled conditions, and only lasts for a few days after being defrosted, with an even shorter shelf-life when it has been removed from the fridge.

Supplies must be used as soon as possible after being prepared.

As doses have to be prepared quickly so medics can get through patients at speed, some will be got ready to use but then left standing if people don't turn up, and may ultimately have to be thrown away or given to someone else at random.

The nurse said: 'It's happening all over London, and probably right across Britain.

'Loads of people are not keeping the appointments their GPs have made for them. The trouble is the vaccine has to be given or it has to be thrown away.

'On Thursday night we had something like 45 people who were booked for jabs but didn't turn up, and didn't let us or their GP know in advance.

'Had we known they weren't coming, someone else could have been slotted in in their place.

'We were left hanging around, and then when they didn't show up, we were faced with the choice of throwing the vaccine away or trying to get it into someone's arm.'I rang some friends and said 'How quickly can you drop everything and get here? Other staff were doing the same.

'Some people we rang were able to come in at short notice and they had the vaccine, but a lot of it had to be thrown away because we can't keep it beyond a certain time.

'I think it's deplorable and a scandal that people are offered a slot and then just don't turn up, and never get in touch.'

The Government is not yet publishing data revealing how many people are turning down or failing to attend appointments to get the vaccine.

Weekly figures show that 1.3million people had been vaccinated by last Thursday, January 7, and daily updates are expected to begin today.

The Government's plan is to vaccinate 13.9million people by February 15, aiming to cover the people most at risk of dying of Covid-19 if they get it, as well as health and care workers.

These include everyone over the age of 70 and people who are on the shielding list because of serious long-term health conditions.

This will require vaccines to be given at a rate of between 2million and 3million per week, a massively ambitious requirement that could be hampered by speed bumps already emerging at clinics.

The nurse added: 'I know from the grapevine it's not just our hospital, it's happening across London, and probably across the entire country.

'We didn't fell guilty calling friends and family - what else were we to do?'

As well as issues with getting all the precious doses used, NHS staff they the IT system they are using to run the programme – called Pinnacle – is unreliable.

The British Medical Association has warned the computer problems were raised with senior managers a month ago but are still persisting.

Patients have been pictured queuing outside of vaccine clinics and staff resorted to making notes with pen and paper when their computers stopped working, The Telegraph reported.

Dr Richard Vautrey, chair of the association's GP committee, said: 'We find we're trying to upload important information and that we can't, or the system crashes altogether.

'It's unacceptable. When trying to get through as many patients as possible, you can't afford to waste a minute, you can't afford for the entire system to be a hindrance.'

Britain's vaccines minister today blamed a shortage of the Covid-19-killing medicine for not having jabs available 24/7 across the country.

Nadhim Zahawi also admitted that said that most people currently had 'about a 45-minute drive' to one of the seven major NHS sites that opened their doors this morning, amid claims the vulnerable face 'gruelling' trips to get their jab because not enough GP surgeries are taking part.