Kittisak Ponpai, head of the Power of Land group, said Tuesday that members of his movement would stage their rally in Si Sa Ket province to protest against today's withdrawal of Thai soldiers from the 4.6-square-kilometre area claimed by both Thailand and Cambodia.
He urged members of the public to join the rally and said that he did not believe that Cambodia would be straightforward in the withdrawal of its own troops.
The International Court of Justice ordered Thailand and Cambodia to pull their troops out of the demilitarised zone covering and surrounding the disputed area a year ago.
Both countries agreed to comply and last week set Wednesday as the date for their joint withdrawal. Both sides will replace their soldiers with border police officers.
Mr Kittisak said soldiers disagreed with the withdrawal and the decision was made by authorities who were not on the ground.
He argues that local people know better what is going in the area and Thailand does not have to follow the order of the international court.
"If we withdraw soldiers, we will make a wrong strategic step," Mr Kittisak said.
"We should not be misled because that could cost us our land."
He denied the movement of his group had a hidden agenda.
About 10 members of his group gathered at Muang Thong intersection in Si Sa Ket yesterday.
They insisted that the 4.6 sq km area of disputed land was Thai territory.
The members also said that Power of Land supporters from other lower northeastern provinces would join their protest today.
Veerayuth Duangkaew, kamnan of tambon Phumsarol, said opinions on the withdrawal were divided among residents in his village.
He said some people expect the withdrawal will lead to the reopening of Preah Vihear temple to tourists.
However, he said that others believed today's redeployment might merely be an act to appease the court and the international community and both countries would not really withdraw their troops.
It was reported that four companies of border patrol police from Sakon Nakhon, Udon Thani and Si Sa Ket provinces will replace Thai soldiers in the disputed area.
Defence Minister Sukumpol Suwanatat and army chief Prayuth Chan-ocha will send in border patrol police from the 23rd Paramilitary Ranger Regiment in Si Sa Ket at 10am.