Putrajaya's decision not to ratify the International Convention on the Elimination of All Forms of Racial Discrimination (Icerd) must be put on record in Parliament, said Umno president Ahmad Zahid Hamidi.
In a statement this evening, Zahid said a mere statement from the Prime Minister's Office on this would not suffice.
He said that this approach does not guarantee that Putrajaya will not change its position later.
"It can only be official with the prime minister's signature and then a motion is tabled in Parliament so it can be recorded in the Hansard," said Zahid.
He said matters of foreign policy must be done according to "procedures" and the opposition will doubt Putrajaya's sincerity until the matter is recorded in the Hansard.
Zahid, who is also the parliamentary opposition leader, said the opposition benched thanked Putrajaya for not ratifying the treaty.
"It is believed that this is linked to the protests against Icerd throughout the country lately.
"It is also believed that the decision was a political manoeuvre in view of the upcoming Rantau by-election," he said.
Prime Minister Dr Mahathir Mohamad had told the UN General Assembly in September that Malaysia would ratify the six remaining core treaties.
Following this, Rembau MP Khairy Jamaluddin queried if ratifying Icerd would affect Article 153 of the Federal Constitution.
This led to objections from Umno, PAS and various Muslim groups on grounds that Icerd would affect the constitutional position of Islam, the Malays, the monarchy and the Malay language.
Malaysia is one of the remaining 14 countries which has yet to ratify Icerd.