Liam Neeson has revealed that he became an American citizen after US supporters helped him cope with the death of his wife.

The Irish actor, 57, insisted he had not forgotten his roots but that the warmth of American well-wishers, following the sudden death of Natasha Richardson, helped him decide to formalise his long-term American residency.

“I'm still a proud Irishman, of course, but I've become an American citizen - I'm very proud of that," he told Diane Sawyer in an interview yesterday on Good Morning America.

Richardson, a Tony Award-winner and member of the Redgrave acting dynasty, died in March after an accident during a skiing trip in Quebec, Canada.

The British actress suffered an epidural haematoma after falling on her head, but declined medical attention as she didn't initially feel unwell. She later complained of a headache and was rushed to hospital before being transported back to a clinic near her home in New York, where she died. The couple had been married for 15 years.

Neeson said that five months on their two sons were "doing good", before adding: "To be honest, we are taking each day as it comes".

The actor, who counts Love Actually, Batman Begins and Schindler’s List among his credits, said he was still getting extraordinary letters of condolences from Americans.

"That is partly the reason why I've recently become an American citizen," he said.

The American acting community famously pulled together to honour Richardson in the days following her death. Pictures of a touched Neeson, flanked by US thespians Sarah Jessica Parker and husband Matthew Broderick, were published around the world when the country's foremost theatre district Broadway dimmed the lights for one minute in the actress's honour.

A string of American acting royalty made public tributes to the star, with Jane Fonda expressing her "utter sadness" and Joan Rivers saying of the couple: "They were totally happy, totally devoted to each other".

Neeson left Ireland for London after attending Queen’s University in Belfast. In 1987 he moved to Los Angeles to further his career. He now lives in New York.

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