Fans who racially abuse footballers online will be banned from grounds under new rules sparked by the outcry over trolling of England players, a move backed by the Premier League.

The Premier League warned on Wednesday that 80% of the abuse reported to its monitoring unit came from outside the UK – but said racists could still be pursued.

Boris Johnson said football banning orders – which can bar offenders from grounds for up to 10 years – would be changed to cover online racism, to keep people found guilty of online abuse away from matches. It is understood the move would have strong support from the Premier League – where one source described FBOs as “under-utilised”.

Announcing the change, Johnson said: “I was appalled by the abhorrent abuse directed towards a number of our footballers in the aftermath of Sunday’s game. More must be done to prevent people being bullied and trolled online.”

The culture secretary, Oliver Dowden, said he had “heard repeatedly from footballers about the devastating impact of racist abuse flooding their social media all hours of the day. It is clear it has a profound impact on them and their young fans. Enough is enough, it’s time to clean up social media.”

Johnson’s spokesperson said there would be a consultation on the change to banning orders, and while the aim was to move as fast as possible, it might potentially not happen before the passing of the long-delayed online safety bill.

“We’ll want to introduce it as swiftly as possible,” they added. A Whitehall source said the change required primary legislation.

It follows racist abuse directed towards Marcus Rashford, Jadon Sancho and Bukayo Saka – three players who missed penalties in England’s Euro 2020 final defeat against Italy.

In data released on Wednesday, the Premier League said its online monitoring system suggested that 80% of abusive remarks against players in the 20/21 season had come from abroad, but said trolls could still be pursued, citing the case of a man in Singapore who was convicted.

Keir Starmer, the labour leader, accused Johnson of trying to “stoke a culture war” by refusing to condemn fans who booed the England team taking a knee but now found himself on the wrong side. He suggested the prime minister had treated racism as “a game”.

Johnson sought to claim he had never condoned the fans’ booing. Devoting almost all his allotted time at prime minister’s questions to the issue, Starmer dismissed Johnson’s claims, saying: “The prime minister isn’t kidding anybody in this house. He’s not kidding the public, and he’s not even kidding his own MPs.”

The exchanges follow disagreements within Tory ranks over how to respond to England players taking the knee before games as an anti-racism gesture, with some MPs and ministers condemning it as “politicised” and others disagreeing.

Another member of the England squad, Tyrone Mings, said messages from some politicians had helped “stoke the fire” of racism.

Referring to a quote before Euro 2020 by Priti Patel, the home secretary, Starmer asked: “Does the prime minister think that it was wrong to criticise the England team’s decision to oppose racism by taking the knee as ‘gesture politics’?”

Starmer then cited Patel, and Johnson’s spokesperson, who before the tournament defended the right of some fans to boo players if they took the knee.

“When senior government ministers and Conservative MPs defend the booing of an anti-racist message, who do they think they are defending, prime minister, and why are they defending it?” the Labour leader asked.

Johnson replied: “I have made it absolutely clear that no one should boo the England team.”

The prime minister was seeking to rewrite history, Starmer said: “Behind them they don’t believe you, and neither do we. We can all see what’s happened here. The government has been trying to stoke a culture war, and they’ve realised they are on the wrong side, now they hope that nobody has noticed.”

Johnson replied saying: “I don’t want to engage in a political culture war of any kind,” which Starmer condemned as fantasy. “Football’s a game; racism isn’t,” the Labour leader said. “Far from giving racism the red card, the prime minister gave it the green light.”

Labour has also accused the government of dragging its feet on the online harms bill. Speaking in an urgent question in the Commons, the shadow home secretary, Nick Thomas-Symonds, said the government had more than enough time to act.

“The racist abuse to which Marcus Rashford, Jadon Sancho and Bukayo Saka have been subjected is disgraceful,” he said.

“Such behaviour has been too common on social media for too long. Social media platforms have had more than long enough to act … Worse still, the bill as proposed will not address what we have seen in the past couple of days – allowing social media companies to set their own terms and conditions will not be enough.”