A Bhumjaithai Party-sponsored bill on cannabis and hemp is likely to be voted down by both the opposition and some government coalition partners if allowing the recreational use of marijuana in the draft remains unchanged.
The third and second readings of the draft are expected to begin next week.
Despite its support for medical use, the Democrat Party remains firm on its stance against allowing the recreational use of cannabis, said Sathit Wongnongtoey, a Democrat MP for Trang, on Thursday.
Since marijuana was taken off the list of Type 5 narcotics and there still isn't any specific law to control it, what is happening now is marijuana is being used "extremely" freely, which is alarming, he said.
Police cannot now arrest those who are selling marijuana freely because it is no longer recognised as an illegal product, while anyone can buy some without an identification card, he said.
Unless the draft already has been amended to clearly state that cannabis will only be allowed for medical purposes, it is unlikely to be passed before the tenure of this parliament ends, if ever, he said.
Anutin Charnvirakul, Public Health Minister, should ask ministry officials how concerned they are now about the apparent worsening drug addiction situation, said Mr Sathit.
Sutin Klungsang, a Pheu Thai Party MP for Maha Sarakham in his capacity as the chief opposition whip, said as the Democrats and the opposition do not support this draft law, it will be 50-50 whether this draft will survive the vote.
The decision now, therefore, lies with the ruling Palang Pracharath Party, which already has made it clear as well that it would not support the bill either if it fails to ensure the control of cannabis to be used for medical purposes only, said Mr Sutin.
"If all parts of the draft clearly state that the use of cannabis allowed is limited to only medical purposes, we will definitely support it. However, if any parts of the bill still open the door to the recreational use of cannabis, we will never vote for it," he said.
The opposition has a clear stance that cannabis must be listed as a narcotic again while still allowed for medical purposes only, he said.
Prime Minister Prayut Chan-o-cha said he will let parliament decide on the bill, when asked whether different stances by different coalition partners on the bill are causing a rift in the coalition.