A third of NHS contact tracers will be laid off within weeks with remaining call handlers redeployed to local authorities amid ongoing difficulties for Boris Johnson's "world beating" scheme.

The Government said it was reducing the number of national contact tracers in England from 18,000 to 12,000 over the next two weeks, in a major overhaul of efforts to curb the spread of the virus.

Non-NHS call handlers will work alongside local public health officials under the new plans.

If national teams cannot contact someone, local public health officials will be able to go and knock on their doors.

Labour welcomed moves to give more support to local authorities but said problems tackling local outbreaks proved the Prime Minister's boast of a "world beating" system was hollow.

NHS Test and Trace was set up to curb the spread of infection rates across England

Thousands of contract tracers were drafted in during the pandemic, with Matt Hancock promising an "army" to track those who have been in contact with Covid-19 patients.

But the system has been plagued by difficulties - with some call centre staff saying they had little to do that one claimed she was paid to watch Netflix.

The boss of Serco, one of the private firms helping run Test and Trace, previously defended the fact that 10,000 contact tracers have spoken to fewer than three people each.

Test and trace is deemed a vital part of keeping infection rates down but recent figures showed that only 72% of coronavirus sufferers' contacts were being reached.

Local public health bosses have pleaded for better data on infection rates in their areas, as a number of towns in the north of England were forced into local lockdowns due to outbreaks.

The new system had been piloted in areas with local outbreaks such as Blackburn with Darwen, Luton and Leicester.

Shadow Health Minister Justin Madders said: “Labour has been calling for a locally-led contact tracing system for months – it’s welcome that local authorities are now finally being given additional support to tackle the virus in their areas.

“But it’s clear Boris Johnson ’s £10 billion centralised contact tracing system is nowhere near 'world beating' as he claims and the system is unable to fight local outbreaks successfully.

“A truly effective system would provide all local areas with detailed data sets, ensure people have support to self-isolate if needed, and give local health officials the help and resources they need to lead contact tracing.”

Test and Trace boss Baroness Dido Harding said the system was one of the largest in the world and it had been "built rapidly" with extra capacity to cope with spikes at the height of the pandemic.

She said: “We have always been clear that NHS Test and Trace must be local by default and that we do not operate alone – we work with and through partners across the country.

"As we learn more about the spread of the disease, we are able to move to our planned next step and become even more effective in tackling the virus.

“After successful trials in a small number of local areas, I am very pleased to announce that we are now offering this integrated localised approach to all local authorities to ensure we can reach more people in their communities and stop the spread of COVID-19.”