Cannabis smokers in Switzerland will soon be allowed to grow up to four marijuana plants each at home to stop them buying drugs on the black market.
In a bizarre twist to the new law, four people sharing a house can grow up to 16 plants - but only if each person tends to their own crop.
The deregulation of Switzerland's already lax cannabis laws has been agreed by four neighbouring regions in the French-speaking part of the Alpine country.
A spokesman for the Neuchatel region said: 'We have agreed these new rules to prevent drugs tourism between regions where the rules are different, and to stop them buying it on the streets.
But one person can not start growing more than four plants just by claiming they live with other people.
In this case, these other people have to actually be cultivating the plants themselves.
Swiss daily Le Matin quipped: 'This basically means that you can grow four more plants for every housemate you have - just as long as they know how to hold a watering can.
The rules will apply in the cantons of Vaud, Neuchatel, Geneva and Fribourg from January 1 next year.