Isuzu will halt development work on a new engine for Opel and pull out of a joint venture in Poland with General Motors, according to Japan's Nikkei business daily.

The truckmaker has been building diesel engines for Opel/Vauxhall's Astra Corsa and Meriva in Poland since 1999 through a JV with GM in which Isuzu has a 40% stake.

The newspaper reported Isuzu plans to halt further development because of the slump in Europe, and it also wants to cut its workforce in the region by around 10%.

Neither automaker commented on the future of the engine development although Isuzu denied it was pulling out of the venture or was cutting its workforce in Europe.

GM once owned almost 50% of Isuzu before selling its stake.