The source said that the EV bus that would be rolled out in October would be a prototype.

Yulon referred questions to Foxconn, which declined to comment.

Foxconn has ramped up its interest in EVs over the past year or so, announcing deals with Chinese EV maker Byton and Chinese automaker Zhejiang Geely Holding Group.

Foxconn aims to provide components or services to 10% of the world's EVs by between 2025 and 2027, and has been in talks with multiple car manufacturers for future cooperation, Chairman Liu Young-way said in October.

Foxconn, formally Hon Hai Precision Industry Co Ltd, announced its joint venture with Yulon last February, with Foxconn investing T$7.9 billion ($282.49 million) and Yulon T$7.6 billion.

($1 = 27.9660 Taiwan dollars)

(Reporting by Taipei newsroom, writing by Ben Blanchard; editing by Jane Wardell)