Jaguar Land Rover owner Tata is set to announce plans to build a flagship battery electric car in Somerset.
People familiar with the matter said the investment would be officially announced on Wednesday.
Sources said the government is providing hundreds of millions of pounds in support.
Some in the car industry have described the plant as the UK’s most important car investment since Nissan came to Britain in the 1980s.
The government has been criticized for its lack of a clear industrial strategy and for lagging behind the United States and the European Union in attracting investment.
Some industry insiders are hopeful that Tata’s battery investment will open the door to more battery investment in the UK, which currently has just one plant in operation next to Nissan’s plant in Sunderland, and one barely on the drawing board in Northumberland.
By contrast, the European Union has 35 factories open, under construction or planned.
The investment could create up to 9,000 jobs in the Bridgwater area.