Gen Boonlert, chairman of Pitak Siam group, said that the rally would welcome all parties, be they yellow or red shirts. The rally would be a gathering of patriots and people loyal to the monarchy without backing from any political party.
The retired army general said the government has failed in governing the country with corruption rampant in various projects. He would unveil evidence supporting his claim.
If the government is allowed to continue, it could inflict further damage on the country, he said.
Gen Boonlert, a classmate of former prime minister Gen Surayud Chulanont at the Armed Forces Academies Preparatory School (AFAPS), admitted that a coup was discussed among his group as many sections could not tolerate how the government is running the country.
Meanwhile, Deputy Prime Minister Chalerm Yubamrung said that he would meet Gen Boonlert today for a private talk but would not discuss politics.
Pol Capt Chalerm said that he believed the upcoming rally would be peaceful and he has ordered police to facilitate the gathering.
Pheu Thai list-MP and red-shirt co-leader Korkaew Pikulthong claimed that red shirt supporters in the North and Northeast were lured by groups of people to join the rally in exchange for Bt300-500 in cash.
He urged supporters of the United Front for Democracy against Dictatorship (UDD), or red shirts, to refrain from joining the rally.