The giant corks are said to be the world's largest. Each has the same volume as 4,001 bottles of wine and stencilled words and images tell the story of the material's use in wine closures

Goolden was on hand yesterday to launch the corks, which were created by the artist Stuart Murdoch for the I Love Natural Cork campaign, at Speakers' Corner in London's Hyde Park.

Corks face stiff competition from screw-caps and plastic stoppers and arguments have raged for several years over the relative merits of the various formats for how a wine ages, environmental impacts and the level of indicence of wine oxidising, or being 'corked'.

'No satisfactory alternative'
Goolden said: "For me, there isn't a completely satisfactory alternative to real cork as a wine bottle closure. Cork is entirely natural and environmentally sound, to say nothing of the romance, history and theatre of the cork."

The giant corks will be on show on The Mall, outside the gates of the Prince of Wales' residence Clarence House, from next Wednesday (8 September).

Prince Charles' 'Garden Party to Make a Difference' is part of his START initiative which aims to encourage people to live more sustainably, and to support local sustainability initiatives.