The boy, who cannot be named due to his age, admitted the manslaughter of Harvey Willgoose, also 15, but denied murder at a court hearing in the northern city of Sheffield.

Willgoose died after he was stabbed in the grounds of All Saints Catholic High School in the city on Feb 3.

A judge ordered that the teenager be held in youth detention until he stands trial on June 30.

The attack is one of a series of fatal stabbings involving young victims.

Prime Minister Keir Starmer has called knife crime a “national crisis”.

“We are utterly heartbroken at the loss of our beautiful boy, ‘Harvey Goose’,” the family said in a statement after visiting the school following their son’s death.

The UK government has announced a series of initiatives aimed at reducing knife crime.

A ban on owning “zombie” style weapons with blades of more than 20cm came into force last September.

Another ban targeting ninja swords – long straight blades of between 14in and 24in, with a sharply-angled tip – will be introduced from Aug 1.

The government said on Friday it would also bring in tougher sanctions for tech platforms for harmful knife-crime content online.

The home office said firms would face fines of up to £60,000 if they failed to remove such content within 48 hours of a police warning, in addition to existing fines of £10,000 for individual tech bosses.

Knife crime in England and Wales has been steadily rising since 2011, according to official government data.

In the year leading up to March 2024, there were 262 murders in England and Wales using a knife or sharp instrument, according to the Ben Kinsella Trust, an anti-knife crime charity.

Of those murdered, 57 were under the age of 25.