England fans have been warned against causing unrest at the World Cup next month by displaying the flag of St George in Russia.
Police say it carries a risk of being "antagonistic" and will be seen as "imperialistic" when the tournament kick-offs in under four weeks' time.
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The head of football policing believes the flags had become "a trophy of choice" for hooligans with around 10,000 England fans expecting to travel this summer.
Three Lions supporters have traditionally carried the flags when visiting host countries with city centers and stadiums turned into a sea of colour.
Deputy police chief constable Mark Roberts urged caution after Russian thugs attacked England fans in Marseilles two years ago during Euro 2016.
He said to The Times: "We really urge some caution about people putting flags out and waving them about in public. People need to be careful. It can come across as imperialistic.
"We would not expect people to come across to this country, get drunk and drape flags on Cenotaph.
"We need to expect the same courtesy when our supporters go abroad."
England name their squad for Russia on Wednesday as Gareth Southgate selects his 23 players who will represent the country next month.