Sales to fleets rose 24.4 per cent in January, fuelling hopes that the business sector may be making a start on the long road to recovery.
The SMMT said the growth in fleet demand provided "encouraging news for a sustaining demand post scrappage".
SMMT chief executive Paul Everitt told Motor Trader: "This month has seen a significant increase in fleet. We always felt it had to happen at some stage."
Last month John Lewis, chief executive of the British Vehicle Rental and Leasing Association said fleet sales may recover this year.
Companies in the downturn had postponed buying new vehicles in order to keep a cap on costs and carmakers have also pulled out of fast-cycle daily rental business, reducing sales.
"Vehicle will need to be replaced soon and with an economic recovery underway, we expect fleet car sales to pass the million mark in 2010, providing a vital shot in the arm for manufacturers," said Lewis last month.
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