“They work very well in many areas and they should be supported. I think that the decision to get rid of them was a real tragedy for this country.”

Mr Johnson said he did not support bringing back grammar schools with “brutal” academic tests for children aged 11, but added: “What I think you could do is have a greater degree of academic competition, academic selection, at various stages in a child’s development.”

“There are ways of doing that, I think, which wouldn’t be hurtful to people, which wouldn’t make them feel like failures, but which would spur competition and get better performance out of our schools.

“And so the principle of academic selection is I’m afraid is not one that we should jettison.

The London Mayor also failed to match Nigel Farage’s decision to go on the popular TV show Gogglebox, which relays footage of families across the country watching television.

The UK Independence Party leader is to appear alongside one of the programme’s most well known couple for a special episode, it has emerged.

Asked if he would be interested in going on Gogglebox, Mr Johnson replied: “What is Gogglebox?” When pushed, he failed to commit to an appearance.

“They work very well in many areas and they should be supported. I think that the decision to get rid of them was a real tragedy for this country.”

Mr Johnson said he did not support bringing back grammar schools with “brutal” academic tests for children aged 11, but added: “What I think you could do is have a greater degree of academic competition, academic selection, at various stages in a child’s development.”

“There are ways of doing that, I think, which wouldn’t be hurtful to people, which wouldn’t make them feel like failures, but which would spur competition and get better performance out of our schools.

“And so the principle of academic selection is I’m afraid is not one that we should jettison.

The London Mayor also failed to match Nigel Farage’s decision to go on the popular TV show Gogglebox, which relays footage of families across the country watching television.

The UK Independence Party leader is to appear alongside one of the programme’s most well known couple for a special episode, it has emerged.

Asked if he would be interested in going on Gogglebox, Mr Johnson replied: “What is Gogglebox?” When pushed, he failed to commit to an appearance.