Pro-cannabis activists on Wednesday began a hunger strike to demand that the government listen to their views, as the Office of the Narcotics Control Board (ONCB) affirmed that parts of the plant would be relisted as a narcotic on Jan 1.

The board said on Wednesday that it would probably consider the recriminalisation of cannabis late this month. If the proposal is approved, the minister of public health would move to have it published in the Royal Gazette, to take effect on Jan 1, 2025.

The date was set to give a grace period of a few months for operators concerned about their legal status to adapt and apply for new licences, the board said.

The law will prohibit the possession, import and sale of cannabis flowers and resin unless one has licences to do so from the Ministry of Public Health.

“After cannabis is relisted as a narcotic, it can be used for medical purposes only and the use must be approved. The ONCB will arrest those who use it for recreation,” the board said.

A spokesperson for the Bhumjathai Party said cannabis was decriminalised only two years ago and people had invested tens of billions of baht in related business.

The activist group Writing Thai Cannabis’ Future said on Wednesday that they would stage a hunger strike until the government agrees to hold hearings to examine the benefits of cannabis.

The group started a demonstration against the recriminalisation of cannabis at Government House on Monday.