By Minami Funakoshi
TOKYO, June 15 (Reuters) - General Motors Co will re-enter the U.S. medium-duty truck market next year with Chevrolet-branded vehicles supplied by Japanese truck maker Isuzu Motors Ltd, people familiar with the matter said on Monday.
The companies are due to make an announcement soon, the people said, declining to be identified because the information is not yet public.
Isuzu's shares rose after a Wall Street Journal report on the deal. They ended up 1.8 percent while the broader Tokyo market was flat.
The long-time partners have in the past jointly developed trucks such as the Chevy Colorado pickup, sold as the i-Series by Isuzu.
GM sold its stake in Isuzu in 2006 after a 35-year capital alliance as it faced financial difficulties, and later announced its exit from the medium-duty truck market when its problems escalated and it filed for bankruptcy in 2009.
It was not immediately clear how many vehicles Isuzu would supply under the original equipment manufacturing deal.
Of the total, 80 percent would be powered by diesel engines and be shipped from Japan. The rest will be assembled at a plant operated by an Isuzu partner in the United States with gasoline engines supplied by GM, the sources said. (Editing by Chang-Ran Kim and Edmund Klamann)