The annual award, celebrating its 20th anniversary, goes to what a panel of poets decides is the best collection of verse published in the United Kingdom and Ireland each year, and is considered to be one of the world's top poetry prizes.

Stag's Leap, published in Britain by Jonathan Cape, was chosen from a record 131 submissions and a shortlist of 10.

"From over 130 collections, we were particularly impressed by the strong presence of women on the list and were unanimous in awarding the 2012 T.S. Eliot Prize to Sharon Olds' Stag's Leap," said Carol Ann Duffy, chair of the judges.

Duffy, also Britain's poet laureate since 2009, called the work "a tremendous book of grace and gallantry which crowns the career of a world-class poet."

Olds wins a cheque for 15,000 pounds ($24,000) for the prize, which is administered by the Poetry Book Society and supported by the estate of leading 20th century poet T.S. Eliot whose works include "The Waste Land".

When her marriage ended, Olds, now 70, promised her children she would not write about the divorce for 10 years. In fact, it took her 15 years to get around to publishing a collection which some critics said was her best yet.

"Olds, who has always had a gift for describing intimacy, has, in a sense, had these poems thrown at her by life and allowed them to take root: they are stunning - the best of a formidable career," wrote Kate Kellaway in The Observer.

The critic added that the collection was surprisingly kind considering its subject matter.

In "Unspeakable", from Stag's Leap, Olds writes:

"He shows no anger,/I show no anger but in flashes of humor/all is courtesy and horror. And after/the first minute, when I say, Is this about/her, and he says, No, it's about/you, we do not speak of her."

Olds was born in San Francisco in 1942 and her first collection of poems, "Satan Says" (1980), received the inaugural San Francisco Poetry Center Award.

She went on to win a string of other prizes and currently teaches creative writing at New York University.

(Reporting by Mike Collett-White, editing by Paul Casciato)

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