Ethnic Malays - constitutionally defined as Muslims - make up 60 per cent of Malaysia's 27 million population, with many of the rest practising Christianity, Buddhism and Hinduism.

Leaders of the United Malays National Organisation (Umno) political party, in response to the perceived threat to their race and religion, demanded on Tuesday that ethnic Chinese and Indian minorities stop questioning their privileges.

"The constitution has enshrined the position and rights of the Malays. There is no need to debate it"

Rafidah Aziz, senior cabinet minister

Rafidah Aziz, a senior cabinet minister who heads the party's women's wing, said: "The constitution has enshrined the position and rights of the Malays. There is no need to debate it."

Hishamuddin Hussein, chief of Umno's youth movement, called for cool heads to prevail on both sides of the racial and religious debate.

"We must remember that we cannot build Malaysia on the basis of narrow-mindedness, chauvinism and extremism. It's a warning to both sides that beneath the surface it's still very fragile."

Affirmative action – criticised by minorities as a vehicle for distributing resources unequally – was introduced following racial clashes in 1969.