Events will be held around the world throughout 2014 to mark 100 years since the birth of Dylan Thomas.
At the National Museum in Cardiff, First Minister Carwyn Jones will open an event which will give details of these celebrations.
Also launching the international festival will be the poet's granddaughter Hannah Ellis, US writer and political activist Kevin Powell, former National Poet of Wales Gwyneth Lewis and harpist Claire Jones.
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Rain clipping the far north through the evening but elsewhere staying dry with some sunny spells.
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Photos taken on Saturday morning show Roald Dahl Plass strewn with empty beer bottles and discarded canisters of laughing gas.