The 434-page book is written by former deputy agriculture minister Yutthapong Jarassathian and some other Pheu Thai MPs.

They planned to launch the book at the park ahead of the coming national book fair.

The officers posted the National Council for Peace and Order notice banning political gatherings as well as the park’s regulation prohibiting political activities. They also asked the MPs to drop the book launch.

The writers claimed that the book is about benefits farmers have gained from the Yingluck government’s rice mortgage scheme.

Yutthapong said the book is also about the plight of Thai farmers after the price of rice plummeted. He had wanted to sell the book and donate money from the sale to farmers.

He said he had no idea which parts of the book are political, as alleged.