Football fans travelling to Euro 2016 have been warned that stadiums, fan zones and transport hubs are "all potential targets for terrorist attacks".

The Foreign and Commonwealth Office urged fans to be vigilant, saying British counter-terror officers are playing a "key part" in foiling attacks.

Updated advice from the FCO said:

The warning comes a day after Ukrainian security services said a French national had been arrested on suspicion of plotting mass attacks at the tournament, which starts on Friday.

The FCO said the updated advice in line with its previous warnings and was not connected to the arrest in Ukraine or any other "new or specific threat".

Commander Dean Haydon, the head of Scotland Yard's anti-terror squad, said they were working with French security forces to play a key role in preparing for the tournament and assessing any threats.

Mr Haydon added fan zones in London would be policed "normally".

"There are different events taking place throughout London, there are fan zones, there are screens going up for people in crowded places and in parks to watch the football. Of course we've got a policing event around that," he added.

"We are policing that as we would do normally and obviously keeping an eye on France."