To celebrate the release of the movie, based on the Roald Dahl book The BFG, the activity will see the dreams of personalities reflected in sculptures and placed in 1.8 metre high jars.
These will form part of the BFG Dream Jar Trail, which will run between 8 July and 31 August 2016. The jars will be found around the UK, as well as in key London landmarks such as Trafalgar Square; St Paul’s Cathedral; The Tower of London, Leicester Square; and the Emirates Stadium as well as the home of Roald Dahl in Great Missenden, Buckinghamshire.
The trail is being jointly organised by Visitlondon.com, Save the Children, The Roald Dahl Literary Estate and film company Entertainment One. After the trail closes, the jars will be auctioned off for both Save the Children and Roald Dahl’s Marvellous Children’s Charity.
Spielberg said: "I'm very excited to be a part of The BFG Dream Jar Trail, share my dream with you and support the valuable work that Save the Children do encouraging and enabling children across the globe to dream big".
Julie Chappell, chief digital officer at Visitlondon.com, said: "The trail will be a wonderful and inspirational addition to the streets of the capital this summer, giving families, Londoners and visitors of all ages the chance to recapture the magic of Roald Dahl’s beloved classic as they explore the city."
To celebrate 100 years since the birth of Roald Dahl, events and exhibitions will be taking place across the capital including The Wondercrump World of Roald Dahl at the Southbank Centre, which invites people to embark on a magical journey and discover the secrets of the writer.
Other celebrities confirmed to be bottling their dreams in jars include Sophie Dahl, granddaughter of the author; illustrator Quentin Blake; Great British Bake Off winner Nadiya Hussain, Arsenal player Per Mertesacker and Paralympian David Weir.
Last month agency Premier created a giant cake and placed it outside Buckingham Palace on the Queen's 90th birthday, in order to promote the film release.