Image caption Walter Breuning said people should never be afraid to die

The world's certified oldest man, whose advice to others included the observation "you're born to die", has passed away aged 114 in the US.

Walter Breuning was old enough to remember his grandfather recounting his part in the slaughter of the American Civil War, during the 1860s.

In his final years in Montana, he was passionate about ending two modern wars, those in Iraq and Afghanistan.

His long good health he put down to a strict regime of two meals a day.

"How many people in this country say that they can't take the weight off?" he asked in an interview with the Associated Press news agency in October.

"I tell these people, I says get on a diet and stay on it. You'll find that you're in much better shape, feel good."

The former railway clerk died of natural causes in hospital in Great Falls.

He had been living in the same retirement home since 1980.

His wife of 35 years, Agnes Twokey, died in 1957.

"We got along very good," Breuning said. "She wouldn't like to spend money, I'll tell you that."

Of his grandfather, he remembered hearing, at the age of three, his recollections of killing Southerners during the Civil War.

"I thought that was a hell of a thing to say," he said.

Reflecting on mortality, he told the Associated Press: "We're going to die. Some people are scared of dying. Never be afraid to die. Because you're born to die."