A group of England football supporters were injured in an alleged attack in Kiev on Sunday night.
The fans, in the city ahead of Tuesday's World Cup qualifier against Ukraine, were reportedly set upon by a gang of around 30 men.
The gang, armed with knives, attacked the England supporters in a coffee shop, leaving three needing hospital treatment.
A Foreign Office spokesman said: "We are aware of incidents in Kiev involving British nationals.
"We are providing consular assistance."
Ukraine head coach Mykhaylo Fomenko later apologised for the incident.
"We are very sorry about this," he told a pre-match press conference at Kiev's Olympic Stadium.