The number of cars built in British factories rocketed more than 42 percent in May compared with 12 months earlier, when Japan's tsunami disaster hit exports of auto parts, industry data showed Thursday.

The Society of Motor Manufacturers and Traders (SMMT) said 141,146 cars were made in May, the month's highest output for eight years.

"Car manufacturing in May hit the highest level of output since 2004 posting 42.2 percent growth, a sizable recovery against volumes hampered by last year's Japanese tsunami," SMMT chief executive Paul Everitt said in a statement.