
"At the rally, the signature campaign will be launched against the Thaksin pardon," multicolour shirt leader Tul Sitthisomwong said on Friday.
Aside from the pardon issue, rally speakers will demand for a stop in the government's favouritism.
Metropolitan Police Region 1 commander Maj General Wichai Sangprapai said he expected the rally to proceed peacefully.
Phayathai police will be in charge of keeping peace at the rally site.