September registrations after 20 days' trading were down 9.1% to 230,249 units on the corresponding period last year.

While all sectors suffered, fleet sales slumped 25%. Year-to-date, the market has slipped 0.2%.

One source said there had been less preregistering as a result of Trade and Industry Secretary Stephen Byers' demand for greater transparency. He cited the French carmakers, followed by the UK market leaders, as the worst offenders.

“At the end of the day, the big players will make the market look reasonable, but I don't believe they will push it to a plus situation on last year,” he said. The fuel blockade had affected sales but most buyers were waiting for price action from market leaders Ford and Vauxhall.