Tesla Motors has extended its agreement with Lotus to help bridge a gap in the production and sales of its Roadster electric car.

Tesla is facing a production shutdown of up to a year after 2011 because of tooling changes at one of its suppliers.

Lotus is providing the California-based Tesla with "gliders," or partially assembled vehicles without the electric powertrain, under a new agreement which will help keep Roadsters in Tesla showrooms for longer than it had previously planned.

The earlier deal with Lotus, for 1,700 gliders, was set to expire in March 2011. With the extension, Lotus will provide at least 2,400 of the partially assembled vehicles.

The agreement has been extended until December 2011, which will help it fulfill orders placed between 2011 and 2012, Tesla said.

A next-generation Roadster is not expected until at least a year after the launch of the lower-priced Model S sedan, which is due to be in production in 2012, Tesla has said.