Ambassador Francis Ricciardone said the government must invest more in educating Filipinos in English, warning that mastery of the language was fast slipping.

''English teaching in the Philippines has declined in the last 15 to 20 years,'' he said.

''If the Philippines won't invest in improving education, particularly English proficiency, it would lose investments, such as outsourcing companies, to countries like China and India,'' he added.

Some legislators recently proposed a law that would designate Filipino, the national language, as the sole medium of instruction in schools.

But Ricciardone said the proposal was ''not realistic,'' noting that such foreign companies as outsourcing firms were already having difficulty hiring ''good English speaking'' Filipinos.

''And that pool of qualified Filipinos is getting smaller,'' he warned.

He noted that in the call center business, merely three to five per cent of applicants had good language skills, and ''even they need further specialized training''.

Outsourcing is a growing industry in the Philippines, with thousands of foreign companies setting up call centers and other backoperation units here.