However, the diesel market rose 6.6% in April, up 4.5% over the year-to-date.
“On five of the last six occasions, new car registrations have received a boost immediately after a general election', says Christopher Macgowan, SMMT chief executive.
“March figures showed that the market had already started to pick up after a disappointing start to the year. April's dip has largely been dominated by MG Rover but it seems that the crisis has not had a significant effect on consumer confidence across the industry. The market remains healthy with registrations expected to hit 2.45m units by the end of the year.”
The Ford Focus continues to top the best sellers list as it has in all but two months in the past five years with 10,922 units sold in April. Vauxhall's Astra saw volumes rise to 9,267 units, up by 75% in April.
The Mini joined the top 10 for the first time since July 2003 with 3,569 sales.
The lower medium segment rose by 7.8% in April to 58,248 units and 4x4 registrations 1.6% to 12,388 units.
Among individual manufacturers, the end of MG Rover's collapse on April 8 left the MG and Rover marques with sales 89% down on the same month a year earlier, at 739 units. Vauxhall led the market with 24% growth year on year to 26,723 units and a 14.5% share, ahead of Ford's 24,786 units, representing a fall of 14.5% and a share of 13.8%.
Among entirely British-built brands, Aston Martin's sales of 172 were 352% ahead of April 2004, and Bentley's 216 units represented a 16.7% rise. Jaguar sales were down 21.8% at 1,884 units, and Land Rover's down 9.8% at 2,803.