Referendum to call for Italy to liberalise cannabis.

Italy is set for a referendum on liberalising the use of cannabis after activists gathered half a million signatures, the threshold required to trigger a public vote.

The referendum, which could be held early next year, proposes to legalise the growing of cannabis for personal use and scrap prison sentences for selling small amounts of the drug.

The petition gathered 500,000 signatures in the first seven days, a result described as "extraordinary but not surprising" by organisers who said the "speed of mobilisation confirms the desire for change on cannabis."

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Pro-marijuana advocacy groups are calling for "15 per cent more signatures" to be added to the petition to ensure it will be accepted for approval by the Supreme Court of Cassation, Italy's highest court of appeal, by its 30 September deadline.

Antonella Soldo, from the association Meglio Legale ('Better Legal') said almost half of those who signed were aged under 25.

The surge in signatures was boosted by a recent law allowing people to sign online via Italy's digital identity system SPID.

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In 2019 the Italian supreme court ruled that the domestic cultivation of small amounts of cannabis for personal use was legal, however it remains illegal to sell and grow cannabis plants on a large scale.

Marijuana has also been permitted for medical purposes since 2007.

Campaign organisers say there are six million recreational cannabis users in Italy.

Activists behind the petition say that legalising cannabis would free up the criminal justice system by ending "unnecessary trials for small amounts of the drug" as well as boosting tax revenues for the state, estimating this value at around €7 billion.

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The cannabis debate is a source of division in the coalition government of Mario Draghi, split generally along right and left lines.

The right-wing Lega and Fratelli d'Italia parties are firmly opposed to any liberalisation - a prospect favoured by the populist Movimento 5 Stelle - while the centre-left Partito Democratico is seen to be dragging its feet on the matter.

If the cannabis petition is accepted by the supreme court, it will be sent to the constitutional court to assess whether the law would comply with the Italian constitution.

If the petition is successful, the president of Italy will set a date for the referendum, likely to be in early 2022 according to Italia media reports.