Internet deliveries of knives banned in war on violent gang crime.
All knives ordered on the internet must be collected in person at a store or a post office, so buyers can prove they are over 18.
The move, which will also affect millions of innocent customers, is among a raft of measures to be unveiled as the Government moves to tackle violence which has seen more than 50 people killed in London alone since the start of the year.
Other action includes tighter gun controls, banning weapons such as zombie knives and the sale of corrosive substances to under-18s, following a spate of acid attacks.
It will also be a crime to carry such harmful products in public without good reason and police stop-and-search powers will be extended.
Under a “two strikes” regime, criminals caught twice with corrosive substances will automatically face a jail term of at least six months.
A government assessment of tougher knife laws published last year recognised the online delivery ban could affect retailers.
But it pointed out that eBay and big stores such as Asda, John Lewis and Wilko do not sell knives online
Other major retailers such as Tesco and Argos stipulate that knives bought online must be collected in-store, to check the age of the purchaser.
The assessment said the fatal stabbing in 2015 of Bailey Gwynne, 16, at an Aberdeen school highlighted “the fatal consequences of not having strong checks in place to prevent under 18s from buying knives online”.
Bailey’s killer told police he bought the knife from Amazon “because they don’t check if you’re 18 or not”.
Victims of the latest crime wave include Tanesha Melbourne-Blake, 17, shot dead in a drive-by attack on Monday.
There have also been a series of stabbings in London, the latest victim being a 13-year-old boy, who is in hospital in a serious but stable condition.
Meanwhile, violent crime is also rising across the country. Police recorded 37,443 offences involving a knife or sharp instrument in the year ending September 2017 – 21 per cent up from 2016 and the highest since comparable records started in the 12 months to March 2011.
Gun-related crime also went up by a fifth year on year, to 6,694 recorded offences.
London’s mayor Sadiq Khan has invited Home Secretary Amber Rudd and MPs to a summit at City Hall to discuss the capital’s crime wave.
A 17-year-old boy appeared before Thames magistrates yesterday, charged with the murder of Israel Ogunsola, 18, and possessing an offensive weapon.
The youth will appear at the Old Bailey on April 10.
Mr Ogunsola was stabbed in Hackney, east London, on Wednesday.