Published Friday, 21 February 2014
The 45-year-old actress died following the incident at a resort in Quebec, Canada.
Ballymena-born actor Neeson told 60 Minutes on American network CBS that he decided to "pull the plug" on her because of a pact the couple had made in case either of them fell into a vegetative state.
He explained how he was told by doctors that she was brain dead.
"When I saw her and all these tubes and stuff, that was my immediate thought ... 'OK, these tubes have to go, she's gone'," the Hollywood star told interviewer Anderson Cooper.
"I went to her and I told her I loved her and just said: 'Sweetie, you're not coming back from this, you've banged your head... we're bringing you back to New York, all your family and friends will come' and that was more or less it."
Neeson said that her death still doesn't feel real and that there are still times "in our New York residence when I hear the door opening... I still think I'm going to hear her".
He also revealed Richardson's heart, kidneys and liver were donated before life support was turned off.
"So she's keeping three people alive at the moment," he said.
"It's terrific... and I think she would be very thrilled and pleased by that too."
The full interview airs on CBS on Sunday.
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