Football banning orders will be changed to cover online racism in the wake of the social media abuse directed at England players, Boris Johnson has told MPs.
The prime minister said the change will mean "if you are guilty of racist abuse online of footballers then you will not be going to the match".
"No ifs, no buts. No exemptions and no excuses," he told the Commons.
Mr Johnson repeated his condemnation of the racist abuse on social media directed at England stars Marcus Rashford, Jadon Sancho and Bukayo Saka.
The trio missed their spot kicks in England's penalty shootout defeat to Italy in the final of Euro 2020 at Wembley on Sunday.
But Labour leader Sir Keir Starmer accused the PM of giving racism the "green light" and trying to stoke a "culture war" over the issue of England players taking the knee before matches to protest against racial injustice.
Mr Johnson's commitment follows on from Labour calling for football banning orders to be extended to cover online abuse.
Reacting to the news, the party's shadow culture secretary Jo Stevens said: "If Boris Johnson wanted to extend Football Banning Orders to include online racism he could have done this a long time ago. When will he put words into actions?"
Banning orders allow magistrates to stop individuals from going to matches in the UK if they are convicted of relevant offences, but currently do not cover incidents online.
They can last between three and 10 years and are largely imposed for violent and public disorder offences.
A petition calling for racists to be banned from matches has garnered more than one million signatures in two days.
Shaista Aziz, Amna Abdullatif and Huda Jawad - who call themselves The Three Hijabis in reference to their heritage and dress - created the petition on Monday.
Mr Johnson met with representatives from Facebook, Twitter, TikTok, Snapchat and Instagram in Number 10 on Tuesday to discuss the issue of abuse on their platforms.
The PM said he "made it absolutely clear to them that we will legislate to address this problem in the Online Harms Bill", warning: "Unless they get hate and racism off their platforms they will face fines amounting to 10% of their global revenues."
Sir Keir challenged Mr Johnson on the issue as the pair clashed at Prime Minister's Questions.
He said the PM "can't have it both ways", pointing out that Mr Johnson at one stage failed to criticise supporters who jeered England players taking the knee.
Responding to Sir Keir asking if he regretted this, Mr Johnson replied: "We made it absolutely clear that no one should boo the England team."
Asked about the matter on 7 June, the PM's spokesman told journalists that England fans should "get behind" the Three Lions but refused to condemn England supporters who had booed players for taking the knee before their Euro 2020 warm-up matches.
"The prime minister supports individuals' rights to protest," the spokesman said, adding: "On taking the knee, specifically, the prime minister is more focused on action rather than gestures."
The Labour leader raised Priti Patel's description of taking the knee as "gesture politics" - and England defender Tyrone Mings accusing the home secretary of having "stoked the fire", asking: "He's right, isn't he?"
"I want to reiterate my support, our support, our total support for our fantastic team and I support them in the way that they show solidarity with their friends who face racism," the PM responded.
"The home secretary has faced racism and prejudice all her career of a kind that he can never imagine, and she has taken practical steps to get black and minority officers into the police in record numbers."
Earlier today Transport Secretary Grant Shapps told Sky News that criticism of Ms Patel's remarks over taking the knee was "unusual" and "odd".
"I thought the comments about Priti Patel were unusual, were odd, because she has spoken very movingly in the House of Commons about her own experiences and suffering from racism," he said.
Sir Keir accused Mr Johnson of "trying to stoke a culture war" on the issue before the tournament and said ministers were now backtracking now that they have "realised they're on the wrong side".
He said: "Why else would a Conservative MP boast that he's not watching his own team? Why else would another Conservative MP say that Marcus Rashford spends too much time playing politics when he's actually trying to feed children that the government won't?
"And why will the prime minister refuse time and time again - even now - to condemn those who boo our players for standing up against racism?
"What is it that this England team symbolises that this Conservative Party is so afraid of?"
The PM said he does not "want to engage in a political culture war of any kind, I want to get on with delivering for the people of this country".
Mr Johnson said Commons is "united" in admiration for the team, adding: "We stick up for them and what we're doing is taking practical steps to fight racism - changing the football banning regime, fining the online companies, and we will use more legislation if we have to - just as we used the threat of legislation to stop the European Super League."
Responding to an urgent question from Labour after PMQs, Home Office minister Victoria Atkins said the issue of football banning orders was "complex" as "some of the trolls that have targeted some members of the team at the weekend are overseas".
Comment: What a charade! It's important to remember that it's highly unlikely that either Johnson or Starmer actually care about racism. They're simply using the issue to try to score points with the plebs.
See also: