Ethan Hawke has opened up about ex Uma Thurman

Nine years after his divorce from Uma Thurman, Before Sunset star Ethan Hawke has opened up about how they fell in love.

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Hawke, 43, told weekly journal Mr. Porter about falling in love with the Kill Bill actress on the set of their film Gattaca.

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He explained: "Gattaca was a great moment in my life and a great moment in Uma Thurman's life, and we fell madly in love and wanted to do all that.

"We tried to be as optimistic as we could be: we all want to believe in love and the possibility of love.

Ethan Hawke and Uma Thurman in 2001. Source: Getty

"The older you get, the more you realise how powerful love is."

Although he was 27 when he wed Thurman, he told the magazine:

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"I don't regret marrying early."

The pair were married for six years before they split in 2004, and share two children together.

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Hawke is now married to their nanny, Ryan Shawhughes. He opened up about their relationship and his views of monogamy, explaining:

"Sexual fidelity can't be the whole thing you hang your relationship on."

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He added: "People have such a childish view of monogamy and fidelity...

"To act all indignant, that your world has been rocked because your lover wasn't faithful to you, is a little bit like acting rocked that your hair went grey."