West Ham's plea for police help at London Stadium turned down
Senior officers have turned down a request from West Ham to police their stadium on matchdays - because the £700m ground does not have a "satisfactory" radio system.
The club requested a police presence in the ground after crowd trouble.
The Hammers only moved to the London Stadium at the start of the season.
"Until there is comprehensive radio coverage officers will not be routinely deployed within it," said the Metropolitan Police's Peter Terry.
Mr Terry, who is deputy assistant commissioner of the Metropolitan Police and in charge of specialist crime and operations, added: "The stadium operators are responsible for the safety and comfort of their customers and staff.
"This issue was highlighted to the stadium operators in October 2014 and the Metropolitan Police Service (MPS) has been in negotiation with stadium operators regarding the provision of Airwave radio inside the stadium.
"During this time, the MPS had spoken to the stadium operators several times to highlight the consequences of not installing such a system.
"The MPS is not able to provide Special Policing Services at this time as it would normally, as there is no satisfactory radio system across the ground."
A stadium spokesman said a decision to install Airwave was "reached in March 2016" and that the procurement and installation of the system "is the responsibility of the police".
He added: "We have fully co-operated and will facilitate any access they require to carry this out.
"The safety of the stadium is paramount and all safety plans are agreed in advance by the police and if there were any significant concerns the stadium would not be licensed."
In response, the Metropolitan Police said it commissioned Airwave to complete the required work in May, and added that it is working with the company to "ensure this work is completed as quickly as possible".
All of Great Britain's emergency services and more than 300 public safety organisations use the Airwave radio system to communicate.
West Ham confirmed that 10 fans were ejected from the stadium during the 4-2 defeat by Watford on Saturday, and there were more disturbances during the first home Premier League game against Bournemouth last month.
West Ham are tenants at the London Stadium, which is owned by E20 and was built to host the 2012 London Olympics.
E20 says it is addressing the recent trouble.
Documents released last year showed the taxpayer - not the club - would foot the bill for much of the matchday operating costs, including security.
Analysis - BBC sports editor Dan Roan
"A blame game is now developing over the violent scenes at West Ham's new home. The club says the stadium's owners and matchday operator need to bolster policing, stewarding and segregation.
"However, it has also been suggested that West Ham could have done more to plan segregated family and singing sections, rather than prioritising the sale of season tickets, with the mix of traditional supporters and thousands of new fans thought to have led to tension."
Subscribe to the BBC Sport newsletter to get our pick of news, features and video sent to your inbox.