The country's biggest car manufacturer Nissan has been ranked Europe's most productive plant for the sixth year running, latest figures revealed yesterday.

Research has shown the company's workforce in Sunderland produced 95 cars per employee last year, proving them the top performers in a study of more than 40 plants across the continent.

The World Markets Research Centre carried out the survey, taking into consideration employees essential to the manufacturing process.

Nissan averaged about 4,500 employees, with 3,122 staff on assembly lines, and made 296,000 cars.

When the Wearside plant was first recognised as Europe's most productive in 1996, the total cars per employee was just 73.

Last year's total represented a six per cent productivity decrease, which bosses said was due to switching from the old Primera model to an updated version.

Toyota's plant in Burnaston, Derbyshire, and Ford's Saarlo uis plant in Germany followed in the table with an average production output of about 87 cars per employee.

Nissan's UK managing director John Cushnaghan said yesterday he was delighted and thanked staff.

He added: ''Once again I would like to pay tribute to all of our employees for their efforts and flexibility in producing yet another strong performance, and also to the strength of our relationships with our suppliers.''