"Let's all get sensible and finally LEGALISE marijuana , for heaven's sake. Decriminalise it, regulate it, tax it ..."
The Jurassic Park actor also look the time to urge New Zealanders to vote in this upcoming election.
"NEW ZEALANDERS ! Kiwis everywhere! Make sure you vote in this vital election.
Easy to do, crucial that you do so."
The actor's post was met with mixed reviews from those on both sides of the referendum debate.
Fellow New Zealand-born actress Rebecca Gibney who stared in Packed to the Rafters commented "Done and yes and yes!!".
Former New Zealand Prime Minister Helen Clarke commented "Legend".
"Do not legalise marijuana, no room for tolerance," another commenter wrote.
Neill was born in Ireland, but moved to Christchurch with his family in 1954.
He recently took to Twitter to share the news of positive coronavirus tests on the set of his new movie, Jurassic World: Dominion.
Resharing the tweet from director Colin Trevorrow, Neill stated: "Yes, roaring and raging and racing back very soon after a brief pause in our Mega Maximum Monumental Milestone EPIC!"
Trevorrow announced an hour earlier the temporary suspension of filming after people on set tested positive for coronavirus.
Universal confirmed the news, issuing a statement and ensuring fans safety of the cast and crew was of the utmost priority.
"Late last night, we were informed that the Jurassic World: Dominion production experienced a small number of positive tests for Covid-19," a spokesperson for Universal said in a statement.
The upcoming instalment will now debut on June 10, 2022 — a year later than planned.
The film, the sixth entry in the 27-year-old series, had just started rolling cameras in the UK when coronavirus started to spread across Europe in March.
The referendum on October 17 gives the public the opportunity to vote on whether the recreational use of cannabis should become legal, based on the proposed Cannabis Legalisation and Control Bill, which details strict controls including a consumption age of 20, limits on THC potency, a levy ring-fenced to boost health services, and a ban on smoking a joint anywhere except at home or at licensed premises.