New legislation which will make it an offence for parents to buy alcoholic drinks for children under the age of 18 will not come into effect until July 2021, junior health minister Paul Blokhuis has told MPs.

The new rules will also make it an offence for friends to buy alcohol in shops or bars on behalf of their younger peers.

Research has shown that 97% of teenagers who drink are provided with alcohol via friends and family, Blokhuis told MPs during Monday’s debate. The new measure is necessary, he said, because there has been little change in alcohol use by younger teenagers over the past four years.

Other measures included in the new legislation are better checks on the the age of people buying alcohol online and tougher rules for supermarkets, which will not be able to offer discounts of more than 25% on beer and wine.

Last week, it emerged that the number of young teenagers hospitalised with alcohol poisoning has barely changed for years but they are getting slightly older.

In total, 279 children ended up in hospital having drunk themselves into a coma last year, with an average age of 15.5, up from 15 in 2007, when records began, RTL Nieuws reported.