The Chinese-based parties in Barisan Nasional should reject any switch in the teaching medium of Science and Mathematics in primary schools unless the Education Ministry can guarantee that students' performance in the two subjects will not decline.

DAP national chairperson Lim Kit Siang said today that there is no reason for the indecisiveness and procrastination by those parties in taking a stand on the proposal.

"The proposal is most inappropriate for Chinese primary schools in view of their consistently high standard in the two subjects compared to other medium streams, including the English schools before they were abolished in the mid-seventies," he said in a statement.