The bid to reassure the industry follows an announcement earlier this year in a consultation document that subsidies administered by TransportAction PowerShift could be cut.
Currently fleets can apply for grants of up to 75% towards conversion costs to cut emissions. But the proposals suggest new grant levels of 20%, 30% and 50% for the three bands.
The Department for Transport, Local Government and the Regions is analysing responses to a consultation document on how the Powershift scheme could best deliver significant environmental benefits.
But a DTLR spokesman said: 'Support for alternative fuels remains strong, as demonstrated by the reduction in duty on gas fuels announced in the Budget.'
- Government 'green' scheme Motorvate has also launched case studies on fleets using alternative fuels. For more details, go to the Motorvate website.