One of Malaysia's best known academics, Khoo Kay Kim, is under fire for urging ethnic Chinese to give up Putonghua education in favour of Malay and English, as a debate over the issue threatens to spill over into street protests this week. Two powerful Chinese school associations on Friday said they will organise nationwide public protests over the issue, starting today, to emphasise the point that mother-tongue education is guaranteed in the constitution. The right to mother-tongue education is one of the founding principles of the nation and cannot be abolished for political expediency, the two organisations said in a joint statement. They rejected demands by political leaders and academics to abolish the current school system, in which language of instruction effectively segregates students based on their ethnicity. On Tuesday, Professor Khoo, a respected public intellectual, waded into the controversy, saying Chinese and Indians - who make up 30 per cent of the population - must sacrifice the vernacular system in the interests of national unity. 'Minorities must sacrifice for the nation. They must give up Chinese and Tamil education in favour of a single, uniting school education system for all Malaysians,' he said. 'The different school system has divided, not united, the people,' Professor Khoo said, urging that Malay be adopted as the medium of instruction in a merged system, with English as a compulsory subject based on its economic importance. His remarks invited vilification from Chinese community leaders, educationists and Chinese language newspapers. Nearly 90 per cent of Chinese pupils shun national schools, where the medium of instruction is Malay, in favour of 1,200 privately funded Chinese schools where the instruction is in a mixture of Putonghua, Malay and English. About 70 per cent of Tamils go to 543 Tamil schools. This leaves national schools predominantly Malay and Muslim. 'The different races go to their own race-based school system,' Professor Khoo said. 'We have to bite the bullet and make the sacrifice for a single, unified school system.' To strengthen economic competitiveness, the government in 2003 ordered all school systems to teach science and maths in English. Five years on, the authorities claim students' standard of English has improved and want to continue the policy - but it has come under severe pressure from Chinese, Tamils and Malays alike, who want the subjects taught in mother-tongue languages.