TAIPEI, June 1 (Reuters) - Taiwan has given conditional approval for Taishin Financial Holding Co's purchase of Prudential Financial Inc's Taiwan unit, which it agreed to buy last year for T$5.5 billion ($199.41 million).

Taiwan's Financial Supervisory Commission on Tuesday said it had granted approval on Monday but Taishin would have to place its stake in Chang Hwa Commercial Bank in a trust to guarantee its future capital needs.

The U.S. insurer is exiting some Asian markets and in April last year sold its South Korean unit to KB Financial Group Inc for $1.89 billion. ($1 = 27.5980 Taiwan dollars) (Reporting by Emily Chan; Writing by Ben Blanchard; Editing by Nick Macfie and David Goodman )