James Ramsbotham, Chief Executive of the North East Chamber of Commerce, says companies like Nissan need to know whether the UK will remain in the EU.
The head of the Japanese car company, Carlos Ghosn, has claimed they would "reconsider" their position if the UK left the EU.
This would threaten jobs at Nissan's plant in Sunderland, which employs 6,500 people.
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A look ahead at the forecast for the Tyne Tees region.
The Met Office confirm this summer has been cooler and wetter than average
The red panda and Rothschild giraffe were born at the North Yorkshire attraction this summer.