Princess Diana's brother said on Wednesday that he felt he was "walking down a tunnel of grief" as he followed his sister's coffin to her funeral last year.

Recalling the agonizing emotion of that day last September, Earl Spencer, 34, said he could not allow himself to cry while Diana's two "courageous" young sons, Prince William, 16, and Prince Harry, 13, were with him in the procession.Diana's funeral marked the climax of a week of national grief almost unprecedented in modern Britain, a country better known for concealing than for displaying its emotions.

Millions of Britons flooded into central London to pay their respects after Diana was killed in a Paris car crash.

Spencer, the two princes and their father, Prince Philip, walked behind Diana's coffin as the cortege made its slow way through central London to Westminster Abbey past huge, grieving crowds lining the route. "It was harrowing, really," Spencer told BBC television in an interview. "I was walking down a tunnel of grief and you could feel the intensity of that grief every footstep."

Spencer paid tribute to the way the two young princes had helped him through his ordeal.

"I'd have been in tears if they hadn't been there and, being a generation senior to them, I couldn't cry if they weren't.

"But it was horrendous. My admiration for those two boys is without bound now. How they could have got through it - it's the most amazing display of courage that I'll ever see."