CHATHAM, Ont. — Layoff notices have been issued to the remaining 345 employees at the Navistar truck plant in Chatham, Ontario.

The layoffs are due to take effect June 27th -- three days before the workers' current contract expires.

The company is required by law to issue the notices.

Bargaining on a new contract is expected to start early next month.

Already this year, Navistar has had two rounds of layoffs covering almost 700 workers at the plant.

The heavy truck industry is being hit hard by the U-S recession and the slumping Canadian economy.

Last year, rival Stirling Truck announced the closing of its plant in St. Thomas, Ontario, resulting in the loss of about 2,000 jobs.