French President Emmanuel Macron condemned on Saturday violence that broke out between football fans on a motorway on their way to the French cup final that left 30 people hurt and a supporters' bus burnt out.

The clashes broke out at a toll gate between fans of Lyon and Paris Saint-Germain (PSG) on their way to the evening's match in the northern city of Lille, which Macron said he would be attending.

The incidents struck 60 kilometres (40 miles) from Lille, where the final was being played because Paris's Stade de France is being readied for this summer's Olympics.

The clashes involved about 100 Lyon supporters and 200 PSG fans, a police source said.

A source in the regional police authorities said 20 supporters were lightly wounded.

Northern region police prefect Bertrand Gaume said eight officers were also hurt.

He said one group of supporters got out of their bus and attacked one carrying rival fans, who threw smoke bombs.

"There were very violent brawls" before police intervened, Gaume said, adding that one bus was left burnt out.

Traffic on the major north-south A1 highway was interrupted in both directions.

Mingling with the public in nearby Tourcoing ahead of the game, Macron said he "condemns all violence with the greatest firmness", adding: "I hope that things will go as normally as possible this evening."

Olympique Lyonnais (Lyon) said in a statement it "condemns this violence".

In Lille, there was a heavy police presence as fans of the rival teams mingled all day without incident ahead of the match that kicked off at 9:00 pm (1900 GMT).

The regional police authority said 1,000 officers were on duty in the town and a further 1,000 in the stadium.

The local authorities had also put in place a number of measures for the high-risk match.

Fans were forbidden to move "outside the areas reserved for them" near the stadium until 04:00 am local time on Sunday, and authorities banned the public consumption of alcohol "in a glass or metal container" until the same time.