The campaign for extended daylight hours is expected to gain a boost this week with an endorsement from the Government's official tourism strategy.
The strategy, due for publication at the end of the week, will say that so-called "double summertime" should be considered as part of a drive to increase tourism to the UK.
But sources at the Department for Culture stressed that any change would be dependent on the agreement of devolved authorities, including in Scotland where many are opposed to a move which would make their mornings darker.
Under "double summertime", the UK would switch the clocks forward an hour from Greenwich Mean Time (GMT) in the winter and then put them a further hour forward in the summer. It would mean the sun rising an hour later than is currently the case, but remaining up for an hour longer in the evenings.
Supporters claim a change could add millions to Britain's earnings from tourism and save thousands of tonnes of greenhouse gas emissions as people turn their lights on later.
But opponents say it would make life more difficult for early-rising farmers, increase the number of road accidents and make it more dangerous for children travelling to school.
Prime Minister David Cameron last year said he was ready to consider the proposal, adding: "The argument will be won when people across the country feel comfortable with the change."
Conservative MP Rebecca Harris, who has tabled a private member's bill calling for daylight hours to be shifted, told The Sunday Telegraph: "The tourism industry has been crying out for extra daylight saving for years. It could extend the tourist season and boost the economy by up to £3.5 billion a year.
"And we would have longer, lighter evenings."