The football child sex abuse scandal is one of the biggest crises in the history of the Football Association, says chairman Greg Clarke.

More than 20 ex-footballers have made allegations of child sex abuse, with several police investigations and an FA review started in response.

Clarke said he was “angry” that “1990s society was sleep walking and we were part of that problem”.

Police have received more than 250 calls relating to abuse allegations.

In addition a hotline set up by children’s welfare charity the NSPCC last week in response to the scandal received more than 50 calls in its first two hours.

The government has called a meeting with police and the FA over the issue, and Culture Secretary Karen Bradley told the Commons the national child abuse inquiry headed by Professor Alexis Jay may include abuse in football as part of its remit.

She added ministers are writing to national sporting bodies, asking them to “redouble their efforts” in child protection.

The FA review will look at what officials and clubs knew, and when.

Clarke, who defended the FA inquiry from criticism it should have a wider scope, said: “The moral consequences of failing to deal with some of these issues in the past we must get to the bottom of.”

Several former footballers have waived their right to anonymity in order to go public and raise awareness of alleged historical abuse in football, winning praise from politicians, sport administrators and abuse charities.

At least eight police forces are now investigating allegations of historical sexual abuse.

Asked if it was the biggest crisis in the FA’s history, Clarke told BBC Sport: “I think it’s certainly the biggest one I can remember.”

And asked if the FA acted quickly enough, he added: “I think we’ve acted very quickly, to be frank.

“The main thing to do is not to encumber the criminal investigations of the police by tainting their evidence.

“We’ve agreed with the police that we won’t talk to any of the victims formally, because they have to talk to them, they have to take statements and we’re not allowed to interfere in that process.”

Clarke said he would not be speaking to any of his predecessors so as not to “taint the evidence”. He said QC Kate Gallafent would lead the inquiry.

“I don’t want to be accused of turning this into an old boys’ inquiry, where all the people in football are talking to each other to make sure it’s a manageable outcome,” he said.

“She will lead it, it will be her conclusions, we will act upon those conclusions and those conclusions will be disclosed.”

Was there a cover-up?

Clarke said he “really didn’t know” and was “not ruling out anything because I haven’t got any facts yet”.

“I think institutionally, all organisations in the old days used to protect themselves by keeping quiet and closing ranks,” he said. “That’s completely inappropriate and unacceptable today.

“I don’t think we can ever say things are clean, because our job is to be paranoid about the safety of children in our game. Every year, we need to assume that bad things are happening and make sure our processes, training and investment are as good as they can be.

“We do that every year, overseen by the NSPCC. You’ll never see complacency at the FA.”