Children as young as five who are close contacts of someone with Covid-19 will need to take daily lateral flow tests from today despite an apparent shortage of the rapid test kits.

For the second day running those trying to arrange a delivery of the home tests are being told the service is unavailable - despite new rules coming into force that now require close contacts of Covid19 cases to report the results of lateral flows for seven consecutive days while a shortage of PCR appointments has also been reported in England today.

The new testing policy applies to adults who are fully vaccinated, alongside children aged five to 18 and those who can't have a jab for medical reasons and does not matter which strain of the virus - Omicron or not - that they've come into contact with.

Problems with supplies of the home test kits first emerged on Monday when the government website began displaying a message stating that there were no tests available for home delivery - while Boris Johnson who was asked about the supply issues during a visit to a vaccine centre yesterday afternoon told people to try their nearest pharmacy or shop if they needed them.

Last night the UK Health Security Agency said that due to 'exceptionally high demand' the ordering service online had been suspended and it too advised people to collect home test kits from pharmacies instead if they required them.

Ministers, including the Health Secretary Sajid Javid, continue to insist that there is no shortage of tests and issues instead surround their delivery with extra capacity being added to the service as a matter or urgency. But as people rush to get their hands on seemingly limited supplies pharmacies across the country are now too reporting that they've run out of stock.

High demand is also being blamed on a temporary shortage of in-person PCR appointments with the government website at one point this morning reportedly showing no available slots anywhere in England. More test slots have since been released, say officials.

Up until now close contacts of those with the new variant have been told to isolate for 10 days even if their PCR test returns a negative result but as part of efforts to reduce the pressures on people's every day lives, while also trying to break chains of transmission, daily testing is to replace existing requirements for Omicron contacts to self-isolate.

Instead, from today, those who have had either two or three jabs and children above the age of five who are identified as being close contacts by staff at NHS Test and Trace can remain clear of isolation providing they take a daily rapid test and report the result online or by calling 119.

Despite those trying to order free boxes of the rapid tests getting messages saying home kits are unavailable, Boris Johnson insists there is a 'ready supply' of lateral flow tests and those not able to order online should try their nearest shops or pharmacies if they need them.

Close contacts, say the government, will be reached via a phone call, email, text or through the Test and Trace app and the requirement to take the daily tests will, from Tuesday, apply to those who have come close to either Omicron or other strains of the virus such as Delta or Alpha.

The rules do not apply to children under five who are exempt from self-isolation and do not need to take part in daily rapid lateral flow testing.

Close contacts of people who have tested positive for coronavirus are at a higher risk of going on to develop the virus themselves and with one in three people asymptomatic, daily testing can help ensure people are not unknowingly passing the virus onto others.

Reporting daily test results will also help health officials, says the government, understand how and where strains of the virus are spreading in the weeks ahead as it attempts to significantly expand the Covid booster programme before the end of the year.

Unvaccinated adults are not eligible for this new daily testing policy and must continue to self-isolate for 10 days if they are a contact of someone who tests positive for Covid 19 whether it is the Omicron strain or not.

Dr Jenny Harries, UK Health Security Agency CEO said: "If you are identified as a contact of someone with Covid-19, taking a rapid daily test – and only needing to isolate if it is positive – will help reduce the spread of the virus and minimise its impact on our everyday lives over the coming weeks and months. Rapid tests are freely available in pharmacies and online.

"Our latest analysis shows that boosters provide the best protection against the Omicron variant, please go forward when you are called. If you haven’t had any vaccine, a first and second dose still gives you protection against becoming seriously unwell. Don’t worry about stepping forwards now – you will be warmly welcomed by our vaccination staff and I would strongly advise you to get vaccinated as soon as possible."

Anyone who has one of their seven daily tests come back positive or who develops symptoms should self isolate straight away and take a PCR test to verify the result.

If that PCR is positive you must self-isolate for 10 days from the day of the positive lateral flow test or from when you first developed symptoms but if it is negative a close contact can leave self-isolation and resume taking the rapid tests for the remainder of the seven days.

This new system will be 'guidance rather than law initially' says the Department of Health and Social Care but the government has pledged to keep this under review.

Today's debate in Parliament over the new restrictions is expected to see a number of Conservative MPs oppose the Prime Minister's Plan B proposals.

With Labour's backing the measures are expected to still be approved but an estimated 75 Conservatives could resist Boris Johnson's plans in particular for NHS Covid passes and the requirement to display vaccine status or a negative lateral flow result before entering larger venues.

Among the Kent MPs intending to support the introduction of Plan B restrictions is Sittingbourne and Sheppey MP Gordon Henderson.

He said: “I will be supporting the extra measures being put in place. Quite frankly I don't see them as being too onerous. Most people are already wearing masks in any case; as to Covid ‘social’ passes, most nightclubs are already doing this and implementing restrictions; so frankly I don’t see anything to object to.”