The Royal British Legion is asking social media users to remind their followers and supporters about the two-minute silence on Remembrance Sunday with a ‘Thunderclap’ which will reach more than one million people.

It believes it is the first UK charity to use the social media tool, which issues an identical message simultaneously on the Twitter and Facebook accounts of those that have signed up to support campaigns on the Thunderclap website.

For the Thunderclap to be sent an initial target number of supporters has to be met. The Legion’s target was 500 which it has surpassed with 3,658 people signed up so far. Thunderclap predicts that this means the message will reach 1,329,279 people.

At 9am next Sunday Thunderclap will send the following message, on all the Facebook and Twitter accounts that have authorised it to do so:

“I won’t forget to Remember on 11.11.11 Will you? #2Minutesilence”

WaterAid has also started a Thunderclap page asking people to support its film set to be released on 19 November, which is World Toilet Day.