YouGov said the ban was a key factor in triggering attempts to quit

The YouGov poll also suggested that 27% of smokers north of the border have cut down since the ban on smoking in public places was introduced in March 2006.

The study was conducted to mark the 25th anniversary of No Smoking Day, on Wednesday.

A total of 2,126 people were surveyed across the UK, with 185 respondents from Scotland.

The research suggested that 18% of smokers in Scotland planned to stop on Wednesday, with the ban proving a key factor in triggering quit attempts.

Scotland banned smoking in enclosed public spaces on 26 March, 2006.

Get help from your stop-smoking service and you're up to four times more likely to succeed Dan Tickle No Smoking Day

It is predicted that more than 2.25 million smokers across the UK - or 19% - will take part, making it one of the biggest No Smoking Days.

This year's campaign, The Great No Smoking Day Challenge, will see events taking place across the country, with local stop smoking services, employers, GPs and others providing help, support and advice to those who are ready to stop.

Dan Tickle, the chief executive of No Smoking Day, said: "If you're ready to quit, there's never been a better time. "Don't forget the free local help that's available.

"Get help from your stop-smoking service and you're up to four times more likely to succeed."