The UK’s daily coronavirus testing capacity is set to more than double with the opening of two new “megalabs” in early 2021, the Government has announced.

The two laboratories, one in Leamington Spa and another in Scotland, will together be able to process up to 600,000 samples a day when operating at full capacity, according to the Department of Health and Social Care (DHSC).

The announcement comes amid the news that Boris Johnson is self-isolating after being in contact with an MP who has since tested positive for Covid-19.

The Prime Minister, who was admitted to intensive care with coronavirus in April, attended a 35-minute meeting on Thursday alongside MP for Ashfield Lee Anderson, who received a positive test result on Sunday.

Announcing the two new “megalabs”, the Government said the daily testing capacity of 300,000 in each lab will mean faster turnaround times for results.

The latest data on the Government’s coronavirus dashboard shows capacity on Sunday was at an estimated 519,951 – with 379,955 tests actually processed.

As well as processing Covid-19 tests, these new diagnostic facilities will be used for critical illness including cancer, cardiovascular and metabolic diseases.

Health Secretary Matt Hancock said: “We didn’t go into this crisis with a significant diagnostics industry, but we have built one, and these two mega labs are another step forward.

“Transforming the UK’s diagnostic facilities is not only essential to beating this virus, but it is necessary to build back better – so we are better prepared in future for testing on a massive scale.”

Scotland’s health secretary Jeane Freeman called the Scottish lab an “important step in our fight against the virus”, but said its location is yet to be confirmed.

“The location of the megalab in Scotland is still to be confirmed and we are working closely with our counterparts in the UK Government on this,” she said.

On Sunday, the Government said a further 168 people had died within 28 days of testing positive for Covid-19.

As of 9am on Sunday, there had been a further 24,962 lab-confirmed cases of coronavirus in the UK, according to Government data.

On news the Prime Minister had been advised to self-isolate, a Number 10 spokesman said Mr Johnson was “well” and does not have any coronavirus symptoms.

MP for Ashfield Mr Anderson said on Facebook that he began experiencing symptoms of Covid-19 on Friday and, after being tested on Saturday, received a positive result on Sunday morning.

“The Prime Minister will follow the rules and is self-isolating,” the Number 10 spokesman said.

“He will carry on working from Downing Street, including on leading the Government’s response to the coronavirus pandemic.”

Elsewhere, the UK is set to become the first country to run final-stage trials of a Covid-19 vaccine being developed by a company owned by Johnson and Johnson.

The phase-three trial of the vaccine, from pharmaceutical company Janssen, starts on Monday and will be the first of its two-dose study.

The jab has already undergone phase one and two trials, and interim analysis of the single-dose study suggests the Covid-19 vaccine candidate induces a robust immune response and is generally well-tolerated.

For the two-dose study, researchers are aiming to recruit around 6,000 UK participants – from a total of 30,000 people globally – at 17 sites across the country.

Meanwhile, the NHS announced it is to set up more than 40 specialists clinics in England for those suffering with the long-term effects of coronavirus.

The 43 clinics will bring together doctors, nurses, therapists and other NHS staff to assess those experiencing so-called long Covid, which can cause continuing fatigue, brain fog, breathlessness and pain.