London police were on Thursday gearing up for one of their largest operations in recent years, a deployment of several thousand officers to keep the peace when far-right activist Tommy Robinson and pro-Palestinian groups hold duelling weekend marches.
London's Metropolitan Police will deploy 4,000 officers on Saturday -- alongside horses, dogs, drones and helicopters -- across the capital, which is also hosting the FA Cup Final on the same day.
Live facial recognition will also be used for the first time in a policing operation around a protest.
The force has imposed various conditions on the two demonstrations, over timings and routes, and for the first time made organisers responsible for ensuring invited speakers do not break anti-extremism and hate speech laws.
Meanwhile, the interior ministry has already blocked seven people from travelling to Britain from overseas for Robinson's "Unite the Kingdom" event.
The former football hooligan turned anti-immigration agitator, born Stephen Yaxley-Lennon, drew up to 150,000 people into central London in September -- many draped in English and British flags -- for a similarly themed rally.
Clashes between some participants and police erupted later in the day, with dozens of arrests and officers injured.
Fifty unidentified suspects are still being sought for alleged offences that day, according to the Met.
Meanwhile groups that make up the Palestine Coalition in Britain have held more than 33 large protests since October 2023.
Recent criminal cases have seen suspects charged after shouting "death to the IDF (Israel Defence Forces)" and "globalise the intifada". 'Risks of disorder' The Met estimates around 50,000 people will attend Robinson's rally, with 30,000 expected at the pro-Palestine rally being held to mark Nakba Day , commemorating the 1948 displacement of Palestinians during the creation of Israel.
The twin demonstrations follow a spate of violent attacks targeting London's Jewish community, which contributed to the UK's terrorism threat level being raised two weeks ago to the second highest "severe" level.
Briefing the media Wednesday, the Met's deputy assistant commissioner James Harman said planning for the policing operation, which is set to cost £4.5 million ($6 million), had been ongoing for months.
"The scale of the operation is unprecedented in recent years," he said, noting 660 officers would be drafted in from outside the capital, costing £1.7 million.
"It now falls to us to deploy very significant resources onto the streets of London to put the policing plan into effect and to keep those groups with opposing views apart."
Harman noted various factors "give us significant cause for concern", with Saturday's FA Cup Final at Wembley in northwest London between Chelsea and Manchester City an added complication.
"Whenever significant numbers of football fans are in close proximity to each other there are also risks of disorder that need to be managed," he added.
"We also need to be mindful of the history of football hooligan groups supporting causes fronted by Stephen Yaxley Lennon," Harman said.
He added the lack of other professional football matches happening nationwide Saturday "increases the likelihood of those groups travelling into London to join his rally".