Lega and Fratelli d'Italia tried to block cannabis referendum after 630,000 people sign petition.

The prospect of Italy holding a referendum on decriminalising cannabis was at risk on Wednesday after the right-wing Lega and Fratelli d'Italia (FdI) tabled a "suppressive amendment" aimed at scuttling the move.

The two parties had attempted to block the progress of a petition in favour of the referendum on liberalising the use of cannabis - signed by more than 630,000 people - arguing that the government should not have granted campaign organisers a one-month extension to collect additional signatures.

However the motion was rejected by the centre-left Partito Democratico (PD), the populist Movimento 5 Stelle (M5S) and the liberal +Europa parties.

The centre-right Forza Italia - an ally of the Lega and FdI - chose to abstain from voting, reports Italian newspaper Il Fatto Quotidiano.

The referendum would propose to legalise the growing of cannabis for personal use and scrap prison sentences for selling small amounts of the drug.

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The attempt to obstruct the passage of the referendum was described as "shameful" by Vittoria Baldino of the M5S, while Riccardo Magi of +Europa said: "The gravity of the Lega's parliamentary initiative is disconcerting."

Giuditta Pini of the PD wrote on Twitter that if the petition had been blocked the 630,000 signatures would have become invalid, "preventing the country from expressing itself."

Activist Marco Cappato of the Luca Coscioni association, one of the groups behind the cannabis campaign, slammed the move as attempted "sabotage" and "dirty tricks", while his colleague Marco Perduca warned: "The coup is foiled for now", thanks to "those who voted solidly against it."

Background to cannabis petition in Italy

Over the course of a week in September weed advocates gathered half a million signatures, the threshold required to trigger a public vote, in a petition calling for a referendum to liberalise the use of cannabis.

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

Pro-marijuana groups behind the campaign were then given an extra month to gather signatures - with the 30 September deadline moved to 31 October - before submitting the petition for approval by the Supreme Court of Cassation, Italy's highest court of appeal.

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Activists 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.

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

Cannabis debate in Italy

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.

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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, with the Lega and FdI staunchly opposed.

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.