LONDON - Registrations rose 13.1 percent in the first quarter to 622,562, helped by an 18.5 percent surge in March.
Some of March's rise was due to a new tax starting on 1 April.
Roger King, acting chief executive of the industry association SMMT, said some dealers may have 'brought forward a small percentage of registrations to avoid payment of the government-imposed £25 ($41) first registration fee.'
The Ford Escort was the top seller (34,741 units), followed closely by the Ford Fiesta (34,405), Vauxhall Vectra (28,358), Ford Mondeo (27,913) and Renault Megane (23,654).
Cars built outside the UK accounted for 66.8 percent (416,243 units) of total sales, up 1.5 percent on the same period last year. Of those, 547,461 units came from other western European countries.