TAIPEI, Mar 20 (AP) -- Taiwan is considering abandoning its long-standing policy of recognizing Mandarin Chinese as the island's only official language, the premier said Tuesday, in a move that would likely anger rival China.

Su Tseng-chang said the Cabinet is examining a draft for a "National Language Development Act" to promote the use of local dialects and prohibit linguistic discrimination.

"Taiwan is a plural society, and all languages should have equal standing and be respected and supported," Su said, indicating an intention to confer equal status on the Taiwanese dialect of Chinese, as well as Hakka, another Chinese dialect.

Such a move would likely be renounced by Beijing, which regards Taiwan as part of its territory, and opposes any efforts by the island's leadership to loosen cultural and other bonds.

Taiwanese is widely spoken by descendants of Chinese immigrants who arrived on the island in the 17th and 18th centuries, but is less well known by the families of people who fled to the island in 1949 after the defeat of Chiang Kai-shek's Nationalists at the hands of the Communists.

The earlier Chinese immigrant descendants make up the core constituency of Su's Democratic Progressive Party -- many of whose members favor Taiwanese independence.

In contrast, most 1949 immigrant families support the Nationalists and favor its plank of eventual unification with Beijing.

Su's announcement is consistent with recent efforts to distance Taiwan from mainland China in the run-up to this December's legislative elections and March 2008 presidential poll.

Other DPP moves included scrapping a government body charged with supervising eventual unification with the mainland and attacking the legacy of Chiang, who was an avatar of the unification doctrine.

President Chen Shui-bian made promotion of local dialects one of the centerpieces of his campaign when he first ran for Taiwan's top office in 2000. Since then he has frequently used Taiwanese in speeches, particularly when appealing directly to his core DPP constituency.

In the 1950s and '60s, Taiwan government policy banned the use of Taiwanese and Hakka in schools and radio broadcasts, but that prohibition was gradually set aside.

Mandarin was made China's official language after a series of student protests in 1919, and achieved the same status in Taiwan when the Japanese were forced from the island following their defeat in World War II.

The indigenous dialect of Beijing and other parts of north China, Mandarin is vastly different from Taiwanese, which is native to the mainland's Fujian province, the source of the vast majority of pre-1949 Taiwanese immigration.