Boris Johnson said he understood “people’s strength of feeling” on football and club ownership, after protests caused Manchester United’s Premier League clash with Liverpool to be postponed.

Fans broke into the Old Trafford stadium ahead of the game on Sunday and invaded the pitch, in a protest against United’s American owners, the Glazer family.

Bottles and barriers were thrown at Greater Manchester Police (GMP) officers outside the club’s home ground, leaving two injured, with one needing hospital treatment.

Asked about the scenes on Sunday, the Prime Minister told reporters during a campaign visit to Hartlepool: “I don’t think it’s a good idea to have disruptive behaviour, demonstrations of that kind.

“But on the other hand, I do understand people’s strength of feeling.

“And I think that it’s a good thing that we have been able to do things that make it pretty clear that the European Super League is not going to be appreciated by the people of this country, or by this Government.”

The Red Devils were among 12 clubs that last month signed up for the breakaway European Super League, which collapsed within 48 hours due to huge, unrelenting pressure.

Those plans brought anger against the Glazer family, with fans congregating at both Old Trafford and the Lowry, the team hotel in the city centre, to demand change ahead of Sunday’s clash with Liverpool.

Sports minister Nigel Huddleston said the violence caused by a “small minority” of fans was “unacceptable”.

He tweeted: “Passions are running high in football but there are ways to protest and make your voice heard without hurting or endangering others.

“We understand the frustrations, but the violence by a small minority of fans at Old Trafford yesterday was unacceptable.”

GMP said one of its officers was “attacked with a bottle and sustaining a significant slash wound to his face, requiring emergency hospital treatment” during the protests.

Foreign Office minister James Cleverly said that while he “cannot condone” fans’ behaviour, it was important to recognise the “frustrations” they have with football clubs.

Mr Cleverly told Sky News on Monday: “Looking at the scenes that we have just seen on the programme, there can’t be an excuse for that kind of behaviour.”

He added: “So I cannot condone the images that we have seen about storming the ground, but we do need to understand the frustrations that fans have, not just with Manchester United, but with a number of clubs across the game.”

The Manchester United Supporters Trust (Must) has since written an open letter to co-chairman Joel Glazer urging the club owners to engage in fan consultation to avoid a repeat of the scenes over the weekend.

The group said: “Let’s be very clear that no-one wants what happened at Old Trafford yesterday to be a regular event.

“What happened was the culmination of 16 years in which your family’s ownership of the club has driven us into debt and decline, and we have felt ever more sidelined and ignored.

“After 16 years not one member of the Glazer family has ever had so much as a conversation with us, the club’s Supporters Trust.”

The plan asks for engagement in the Government’s fan-led review of football governance, the appointment of independent directors to the board to protect the interests of the football club, work with Must and supporters on a fan-share scheme, and consultation with season ticket-holders on significant changes at the club.

Must have asked for a public and written response by Friday.