In a photo which is believed to have been posted by one of the footballer’s friends on Instagram, the four players are pictured in one house with 11 other adults, two children and a baby.
Under government guidelines set out on December 19, those living in Tier 4 areas such as London were not permitted to mix with anyone outside their own household at Christmas.
Tottenham stars Sergio Reguilon, Erik Lamela, Giovani Lo Celso and West Ham’s Manuel Lanzini are believed to have broken Covid-19 rules by spending Christmas together
Across the rest of the country, up to three households were allowed to meet on Christmas Day only.
Tottenham have heavily condemned their players for breaking the rules.
A statement from read: ‘We are extremely disappointed and strongly condemn this image showing some of our players with family and friends together at Christmas particularly as we know the sacrifices everybody around the country made to stay safe over the festive period.
‘The rules are clear, there are no exceptions, and we regularly remind all our players and staff about the latest protocols and their responsibilities to adhere and set an example. The matter will be dealt with internally.’
West Ham said they were ‘disappointed’ to learn of Lanzini’s actions.
Lanzini posted a picture of himself and his family in the same house on Christmas Day
Their statement read: ‘The Club has set the highest possible standards with its protocols and measures relating to COVID-19 so we are disappointed to learn of Manuel Lanzini’s actions. The matter has been dealt with internally and Manuel has been strongly reminded of his responsibilities.’
Sportsmail understands Lanzini has returned a negative Covid-19 test since the photograph was taken and that only Ryan Fredericks in the West Ham squad is currently self-isolating.
It is also understood that the club has undertaken a deep clean of their Rush Green training ground in a bid to keep on top of rising cases of Covid-19 across the country.
Lanzini himself has apologised for his action in a post on Twitter.
The forward wrote: ‘I want to apologise for a bad mistake I made over Christmas and I take full responsibility for my actions. I know people have made difficult sacrifices to stay safe and I should be setting a better example.’
A Met Police statement on Saturday read: ‘We are aware of the image and of the statements made by Tottenham Hotspur and West Ham United.
‘We will make contact with both clubs to establish further details.
‘We remind all Londoners that it is up to all of us to make the right choices in order to slow the spread of the virus.’
Those living in Tier 4 areas must stay at home, apart from limited exemptions set out in law which include work and education. People are not allowed to meet others indoors, unless you live with them or they are part of your support bubble.
The gathering is believed to have taken place in Lo Celso’s house with replicas of the Ligue 1 and Coupe de la Ligue trophies, which he won during his time at Paris Saint-Germain, pictured in the background.
The West Ham forward issued an apology on Twitter for breaking the government guidelines
Both Reguilon (left) and Lamela (right) played in Tottenham’s draw with Wolves while Lo Celso missed out through injury
In another Instagram post on New Years Eve, Lo Celso tagged his location as London
It is not clear where Lo Celso’s house is located but an Instagram post in the same house on New Years Eve tagged his location as ‘London’.
Lanzini posted a picture of himself and his family in the same house on Christmas Day with the caption: ‘Feliz Navidad.’
Lamela, Lo Celso and Lanzini are international team-mates for Argentina while Spanish international Reguilon joined Spurs from Real Madrid in the summer.
Tottenham played Wolves on December 27 with Reguilon and Lamela both featuring while Lo Celso is currently injured. Reguilon played 63 minutes while Lamela came off the bench in the 84th minute.
Lanzini has played in all three of West Ham’s festive fixtures against Brighton, Southampton and Everton.
Reguilon has been named on the Tottenham bench for this afternoon’s match with Leeds while Lamela is not in the squad.
Spurs had their game on Wednesday called off following a coronavirus outbreak at Fulham.
Jose Mourinho called the Premier League ‘unprofessional’ for the last-minute postponement of the match.
Tottenham fans slammed the actions of their players on Twitter with many calling for them to be banned.
Some Tottenham fans suggested their players should be banned for their actions
One tweeted: ‘Lost my respect to Lamela Lo Celso and Reguilon. How could they do this. Should get banned.’
Another added: ‘Lo Celso, Lamela and Reguilon need to be dropped and severely punished. Absolute f****** DISGRACE.’
Reguilon revealed before Christmas that Mourinho had gifted him a suckling pig because he would be spending the occasion by himself
The defender told Spanish newspaper AS: ‘For example on Christmas day, he knows that I am alone.
‘We got to training on the 25th at 3pm and I had a box on my seat. I open it and it was a suckling pig already cooked.
‘He told me, “I know you are alone at Christmas so you don’t have to cook dinner and eat well”.’
Lanzini has featured in all three of West Ham’s festive fixtures against Brighton, Southampton and Everton