Other luminaries to back the campaign include London Mayor Ken Livingstone, television chef and food writer Hugh Fearnley-Whittingstall, secretary of state for trade and industry Patricia Hewitt and BBC news presenter George Alagiah, who is patron of the Fairtrade Foundation.
Archbishop Williams will participate in a Fairtrade Pancake Race, along with the television chef Michael Barry. There will also be breakfasts, tastings and a coffee question time with Hewitt and Nicaraguan coffee farmer Blanca Rosa Molina.
Fairtrade coffee now accounts for 14% of the roast and ground coffee market in the UK, and the Fairtrade Foundation says that the British drink 1.7m cups of Fairtrade tea, coffee and cocoa each day, as well as eating 1.5m Fairtrade bananas a week.
Fairtrade products now cover fresh fruits including pineapples and mangoes, a range of chocolate, honey, sugar and fruit juice.
According to Hewitt: "By choosing Fairtrade products, consumers are making a real difference to the livelihoods of some of the poorest farmers in the world. At a time when coffee prices, in particular, are at such low levels this can make the difference between simply existing and having a sustainable future."
The Co-op supermarket chain has a policy of only stocking certain products if they are Fairtrade approved, such as pineapples, and recently introduced two Fairtrade wines from South Africa. It has also used Fairtrade products in its advertising and was the first supermarket to do so.
Fearnley-Whittingstall said: "I like to buy food produced by people with names -- not the faceless multinational corporations. Here in Dorset, that means farmers' markets and local farm shops. But for more exotic ingredients, Fairtrade gives me the same kind of guarantee of responsibility and traceability."
Fairtrade Fortnight 2003 is being launched this morning at The People's Palace in The Royal Festival Hall. Fairtrade Fortnight runs until March 16.
The fortnight is being organised by the Fairtrade Foundation, which certifies and promotes Fairtrade. It was set up in the early 1990s by agencies including Cafod, Christian Aid, Oxfam and the World Development Movement to respond to the human consequences of collapsing world commodity prices.
The first Fairtrade-marked product, Green and Black's Maya Gold chocolate, appeared on the supermarket shelves in 1994; Cafedirect coffee followed soon after.
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