Raymond Young, deputy secretary of the education and manpower bureau, said tests would go ahead despite opposition from unions. In five years he expects all language teachers to sit for an open exam, but he anticipated that English medium schools will be required to take them earlier.

The language issue is highly emotive and politically sensitive. Parents and employers regard these schools, where all subjects are taught in English, as superior to Chinese schools.

But Mr Young was scathing about the quality of teaching. “English is a foreign language despite 150 years of British rule. We have had English-medium teaching for 50 years, but look at the results - 12-year-olds can’t utter a coherent English sentence.”

The government’s education commission, which has produced a “Blueprint for the 21st century”, said Hong Kong citizens should be trilingual in Cantonese, Putonghua (Mandarin) and English.

The commission ordered 460 secondary schools to prove their English was good enough before being designated as English medium schools. Only 114 have been given that right.

“Call yourself an English school and you’re automatically notches above everyone else,” said Daniel Tse, president of the Hong Kong Baptist University.

Desmond Lauder, Hong Kong director of the British Council, which runs a massive English language teaching programme, said the government had failed to win the public relations battle with parents. It had not conveyed the message of research which shows that children learning subjects in their mother tongue did better than those learning in English; and students in Chinese-medium schools did as well in English as their counterparts.