The 29-year-old, who was raised in Australia and is now based in New York, is the second person to win the award, which was set up in honour of the Welsh poet and is given to the best young writer in the English-speaking world.

Peter Florence, chairman of the judges, praised Nam Le as a “phenomenal literary talent” whose work displayed “a rare brilliance that is breathtaking both in the scope of its subject matter and the quality of its writing.”

The writer, whose short stories take readers from the slums of Colombia to the streets of Tehran, was named the winner at a ceremony in Swansea in south Wales, once Thomas’ hometown.