Mr Forsyth will meet Ernie Dudley, assistant secretary of the Communication Workers Union, on Tuesday to discuss the Bill, the effect of which would be to increase daylight hours on winter evenings at the expense of darker mornings.
The CWU opposes the measure because of the effect on postal workers whose work is concentrated early in the day. Mr Forsyth has lobbied hard against the proposal, which has met opposition in Scotland, where winter daylight is generally shorter than in England.
The campaign against the Bill will step up a gear tomorrow when Sunrise, a consortium of businesses and local authorities opposed to the Bill, publishes an academic report disputing claims that the measure would save lives.
Opponents of the Bill believe they can stop it receiving a second reading on Friday.
However John Butterfill, Conservative MP for Bournemouth West and the Bill's main backer, launched an outspoken attack yesterday on Mr Forsyth, whose conduct in opposing the Bill, he said, "beggars belief".
The Sunrise report, commissioned from the Centre for Occupational and Environmental Health Policy Research at De Montfort University, Leicester, argues that "many of the claims made by the advocates of change cannot be justified on the basis of currently available evidence".
Attacking the claim that lighter winter evenings would cut casualties among children, the report argues: "If the number of kilometres cycled in December-February reached the level for June-August, we might expect 25 additional cyclist deaths. However casualty rates in the winter months averaged 863 per 100 million vehicle kilometres, compared to 499 for the summer months.
"This suggests the real additional death toll could be nearer to 50 deaths each year".
The document also points to the 1968-71 clocks-forward experiment, during which "construction site deaths and injuries rose substantially".
It adds: "Postal workers suffered a 265 per cent increase in road traffic accidents in the same trial, with over one in every 20 postal delivery workers involved in an accident."
Mr Butterfill replied: "The Transport Research Laboratory, which is the Government's own agency, is clear there would be very significant reductions in accidents: over 2,000 accidents involving injuries a year and 110 deaths.
"The Royal Society for the Prevention of Accidents believes these figures are an under-estimate. The AA and the RAC both agree with us."
Last week Mr Forsyth's department said the change would not have a significant effect on road casualties in Scotland.
Although sceptical of Mr Forsyth's analysis, Mr Butterfill added: "Is he saying 'we're all right Jack in Scotland, so let's pull up the ladder'?" That is an astonishing thing for a Minister of the Crown to say."
Referring to the Sunrise report, Kate Hoey, Labour MP for Vauxhall and an opponent of the Bill, said: "This report blows a coach and horses through the Daylight Extra campaign."Reuse content