The Prime Minister is due to set out plans to mark the centenary of the start of the First World War.

David Cameron will give a speech on remembrance in London later.

A poll by independent think-tank British Future, one month ahead of Remembrance Day, found 69% of people believe the milestone will be a once-in-a-generation moment and an opportunity to mark the nation's shared history.

It showed the public wanted to mark Remembrance Sunday 2014, the centenary of the First World War, as a special national day.

British Future is calling for shops to be closed, sports games moved to other days and a longer period of silence to be observed to mark the day.

According to the survey's findings, 83% of respondents think bells should ring across the country after a period of silence, while 87% think all flags across Britain should fly at half mast throughout the day. The poll of 1,782 adults also suggested 54% think major sports games should be moved to other days, with 34% against, while it found an even 45% split on whether shops should close.

Sunder Katwala, director of British Future, said: "The centenary of the Great War should be the next great national moment bringing us together as the Jubilee and Olympics did this year.

He added there was a need to decide how to mark the day, adding: "Should this be a special Sunday where we close the shops and have a football-free day and find ways to bring us together and understand our history and the country we have become?"

Royal British Legion director general Chris Simpkins said: "The tragic events of 1914-1918 have left a deep imprint on the fabric of the nation. As the custodian of remembrance, the Legion will ensure that the centenary will be observed across the UK. The costs of sacrifice and the lessons learned in this dreadful conflict must not be forgotten."

Mr Simpkins said central government should provide support for national and international commemorations, while leaving local areas to arrange their own.