The Thai government is moving to tighten rules around the sale of cannabis, just three years after the kingdom decriminalised recreational use of the popular substance.

Thailand’s Ministry of Public Health on Tuesday night ordered that cannabis use be restricted to medical use only, throwing the estimated $1bn industry into a state of uncertainty.

Government spokesperson Jirayu Houngsub said cannabis had created serious social problems for young people, and the industry, which has boomed in recent years, needed to be scaled back.

“The policy must return to its original goal of controlling cannabis for medical use only,” Jirayu said in a statement.

The order, however, is not law yet.

It will need to be published in the official Royal Gazette to come into force, and the government has not indicated when that will happen.

Thailand became the first country in Asia to fully decriminalise cannabis in 2022, in a move that has been wildly popular with tourists but less so among more conservative Thais.

Thousands of cannabis stores have opened across Thailand in the past three years, although it has remained relatively unregulated despite multiple attempts by the government.

The latest move to restrict cannabis use comes amid wider political turmoil in Thailand.

Last week the Bhumjaithai Party, previously a champion of decriminalising cannabis, withdrew from the government’s ruling coalition due to its mishandling of a border conflict with Cambodia.

The Thai Chamber of Commerce previously estimated that the cannabis trade could be worth $1.2bn by 2025, although experts say it has not reached its full potential due to the uncertainty that has plagued regulation around the industry since it was decriminalised.