A Thai cannabis farmer supports the government's policy u-turn to outlaw the drug.

Medical cannabis tycoon Montri Yiamsoongnern said banning non-prescriptive cannabis would improve social cohesion due to a rise in youngsters using the substance, as well as stopping the surge of tourists smuggling it back to their homelands.

It came as Public Health Minister Somsak Thepsuthin vowed to purge Thailand of recreational marijuana use 'within 45 days'.

Somsak made the declaration after signing on Monday a new regulation restricting cannabis use strictly for medical purposes. Buyers will need a doctor's prescription and a medical certificate to purchase cannabis.

Montri, who is president of the a cannabis enterprise network in Nakhon Ratchasima, said: 'I believe the free cannabis policy introduced in 2022 has led to uncontrolled access among children and youths, which poses a serious threat to the nation's future.

'Meanwhile, law-abiding cannabis enterprises have been hit hard. We are now stuck with unsold stock after losing business opportunities and having purchase orders cancelled following the policy announcement.'

He said he was forced to switch to less lucrative vegetable farming for income after the market was flooded with substandard cannabis products, allegedly causing his business to fail.

He urged government chiefs to create clearer regulations 'so that all parties can move forward correctly'.

The stricter cannabis measures were signed just days after the Bhumjaithai Party withdrew from Thailand's ruling coalition. The party, led by former Public Health Minister Anutin Charnvirakul, had made cannabis legalisation its flagship campaign policy for the 2019 general election.

Thailand decriminalised marijuana in 2022, making it the first Asian nation to do so.

However, the lack of regulations caused a surge in unregulated sales and use, especially in tourist areas like Bangkok, Phuket, and Pattaya.

Government officials are now seeking to outlaw recreational cannabis use by requiring medical certificates to purchase the drug.