PAS and Umno will hold a joint protest against the International Convention on the Elimination of All Forms of Racial Discrimination (Icerd) in Kuala Lumpur on Dec 8.
Perak PAS commissioner Razman Zakaria said the rally was agreed to by the central PAS working committee earlier today.
"We will mobilise all Malaysians to go down to Kuala Lumpur," Razman said at a joint PAS-Umno rally in Pasir Salak, Perak, tonight.
Umno president Ahmad Zahid Hamidi, who was also present there, confirmed that Umno will join the rally.
"I wish to confirm, that Umno will support this rally. This is not a rally by PAS, Umno, or Muslim NGOs. This is a rally of all the ummah (faithful),” Zahid said.
Ratifying Icerd has been a heated issue in Malaysia, with bumiputera groups opposing it as being against the Federal Constitution's special provisions for bumiputera.
The matter cropped up after Mahathir told the UN general assembly in September that Malaysia would ratify all remaining human rights conventions.
Zahid in his speech, said that even though the previous BN government had not ratified Icerd, it had never "oppressed any race or religion".
"Don't be mistaken, on the pretence of equality, they want to sideline Islam, Malays, and the Malay rulers.
"Let us rise and reject Icerd," he said.
Meanwhile, PAS president Abdul Hadi Awang said the rally is part of democracy.
"We as leaders are compelled to be examples of a united ummah. To right what is wrong, not to create chaos.
"We have a right to hold a peaceful rally. Let them witness how many people (support us).
"Compare it. If they dare, they can mobilise their people and compare (the support level)," Hadi told the crowd.