West Ham manager David Moyes believes testing Premier League players twice a week for Covid-19 will help limit its spread as fears grow over a mutant variant of the coronavirus which is believed to be more infectious.
Top-flight players in tier four areas will be tested for Covid-19 twice a week as soon as it is practically possible to do so, the PA news agency understands.
Players in the Premier League have been tested on a weekly basis since the start of the 2020-21 season, but testing at clubs in tier four areas will now revert to the level used during 'Project Restart' in the summer.
Moyes, who contracted coronavirus in September before he made a full recovery, said of testing: "I think it has worked out fine.
"The number of Premier League players who have tested positive has not been a big percentage compared to what maybe there has been elsewhere.
"We're really privileged here and in a great position and very lucky that we do get tested so often.
"I understand if we're going to keep football going, I do believe that we all need to go back to testing twice a week because the virus is becoming so strong, certainly in this part of London, and round here.
"We're really keen that we don't get any virus and try to keep it out. If we move to twice a week, I think it's a good thing.
"But I certainly don't take it for granted. It's a real privilege and we should be thankful that we're in a position to be tested."
The Government placed large parts of south-east and eastern England into tier four last weekend over fears that a strain of the virus is in circulation which is believed to be more transmissible than previous ones.
The Premier League clubs currently in tier four are Arsenal, Chelsea, Crystal Palace, Fulham, Tottenham and West Ham.
The Premier League had said when it cut testing back to once a week at the start of the new season that it would keep testing levels under review.
The league's latest figures were released on Monday night and showed there were seven positive cases out of 1,569 players and club staff tested.
Ipswich are one of a number of EFL clubs who have been forced to postpone matches due to a coronavirus outbreak, and physio Matt Byard has said football "may benefit from a 'circuit breaker".
Positive tests at the Portman Road outfit – including for manager Lambert – led to the postponement on Monday of their League One match at home to Northampton on Boxing Day and the trip to AFC Wimbledon on December 29.
Other EFL clubs who are currently experiencing similar issues include Millwall, Peterborough, Sunderland and Bristol Rovers.
"It's the protocols that have worried me more than anything else," Tractor Boys boss Lambert told BBC Sport.
"I think you're putting people's lives at risk by not getting them tested regularly. It's been shocking.
"I know friends in Bundesliga 3, which is the equivalent of League One, and they've been tested over 50 times since they've been back in pre-season.
"Without our owner, who has paid for two out of his own pocket, we'd have been down to about six testings which is nowhere near enough."
Asked about the possibility of pausing the season now and extending it into June, Lambert said: "Yes you could, because League One and Two – no disrespect, but they don't have too many international players that need to go into the Euros.
"I don't think anybody would have any grievance on that. But there's got to be a safer way, and a fairer way to get through. Whether it's the testing... at the minute, I know for a fact, and I can only speak because I have had it, it's not working."
The EFL said its clubs would be "reviewing and further strengthening their Covid-19 protocols to help minimise the transmission risk" but that this would still only cover mandatory testing where players or staff are showing symptoms.
League-wide testing is conducted at strategic times during the season, with the next set scheduled for the week beginning January 4.
It is understood measures which will be looked at include keeping time in indoor environments on club premises to an absolute minimum, a review of the use of gyms, changing facilities, showers and catering facilities, using multiple coaches or individuals' cars to travel to matches and limiting contact with anyone outside of a household bubble over Christmas.