The Agricultural Land Reform Office (Alro) has been ordered to inspect all land that was initially intended for poor landless farmers and has been taken over by local or national politicians.
It must also find out how these politicians obtained ownership of the land.
Deputy Agriculture and Cooperatives Minister Thamanat Prompow said he has a list of politicians who own Sor Por Kor land, which Alro usually distributes to landless farmers.
Information gleaned from the nationwide inspection will be used to back legal action taken against people who unlawfully own agricultural land, the minister added.
The move comes at a time when the Royal Forest Department (RFD) is inspecting 682 rai of land for encroachment in Ratchaburi's Chom Bung district. This plot is owned by Palang Pracharath Party (PPRP) MP Pareena Kraikupt.
In response to reports the government may try to help Ms Pareena get off the hook in this encroachment case, Capt Thamanat insisted the same standard applies to whoever violates the law.
The RFD, along with the Natural Resources and Environmental Crime Division, on Thursday pressed on with inspections of the controversial 682 rai and is expected to formally file charges against Ms Pareena as soon as the inspection is wrapped up, said Thawatchai Latkrut, director of the RFD's 6th forest resources management office in his capacity as leader of the operation.
The inspection began on Wednesday after the Council of State, the government's legal advisory body, ruled the day before that the authority to take legal action against Ms Pareena lay with the RFD. Earlier agencies seemed confused about who should do the job.
The MP will possibly face charges for violating all three laws, namely the Land Act, the 1941 Forest Act and the National Reserve Forest Act, according to Atthaphon Charoenchansa, director-general of the RFD. However, Ms Pareena insisted on Thursday her land was not encroaching into the forest as alleged and will fight the case to the bitter end.