Both England and Russia could be disqualified from the Euro 2016 tournament if there is further violence by the countries' fans, Uefa warned. The Uefa executive committee told the English Football Association (FA) and the Russian Football Union (RFS) that "it will not hesitate to impose additional sanctions... including the potential disqualification of their respective teams" from Euro 2016 should violent fan disorder continue.

Earlier, the association said it would sanction Russia after fans were filmed charging at and attacking England supporters in the Stade Velodrome in Marseille, during the 1-1 draw between England and Russia. It has not begun disciplinary action against England.

Russia was charged with fan violence, racist behaviour, and letting off fireworks in the stadium. Before the match, England fans were involved in violent clashes in the centre of Marseille with rival fans and local police. One England fan was critically injured in the violence.

The British government has offered to send extra officers to help police England's next match against Wales in Lens on Thursday.

Stade Velodrone violence
An England fan is attacked at the Stade Velodrome in Marseille during the Group B clash between England and Russia Getty images

Uefa said it only has the authority to sanction countries for the behaviour of fans inside stadiums. In a strongly worded statement, it warned of the consequences of further violence by English and Russia football fans: "The Uefa Executive Committee has warned both football associations that - irrespective of any decisions taken by the independent disciplinary bodies relating to incidents inside the stadium - it will not hesitate to impose additional sanctions on the Football Association (FA) and the Russian Football Union (RFS), including the potential disqualification of their respective teams from the tournament, should such violence occur again.

"We urge both the FA and the RFU to appeal to their supporters to behave in a responsible and respectful manner.

"We would also like to publicly voice our support for the work of the French Authorities and security forces for their efforts to deliver a safe and secure tournament in challenging circumstances."