LONDON, United Kingdom?"Love Story" author Erich Segal, whose popular romantic drama coined the phrase "Love means never having to say you're sorry," has died of a heart attack at the age of 72, his daughter said.

Segal, who also wrote the screenplay for the Beatles' animated film "Yellow Submarine," died at his home in London on Sunday, his daughter Francesca Segal said.

The author had been suffering from Parkinson's disease for many years, she said Tuesday.

The United States-born writer was a classics professor at Yale University when he wrote the book "Love Story,? which was made into a 1970 hit film starting Ryan O'Neal and Ali MacGraw.

The movie, which won an Oscar and was nominated for six others, tells the story of a wealthy young man, Oliver, who becomes estranged from his father when he marries Jennifer, a woman from a less privileged background.

But the tale takes a tragic twist when Jennifer develops leuaemia and eventually dies.

Oliver's father has a change of heart when he hears what has happened and races to see him, telling his son he is sorry to hear the sad news.

This is when Oliver replies: "Loves means never having to say you are sorry."

In a 2008 article for Granta magazine, the author's daughter said "Love Story," inspired by a true tale, captured her father's imagination and made him "a world-famous author."

"His agent begged him to put it aside, convinced it would ruin his reputation as a writer of macho action screenplays.

"But it had poured from him in what felt like a single sitting and, although he could not have known to what extent, he knew it was worth fighting for."

"The two monoliths that dominated my father's identity?the peak and the trough of his life?were 'Love Story' and Parkinson's disease," she added.

Speaking at his funeral Tuesday, Francesca Segal paid tribute to her father's tenacity.

"That he fought to breathe, fought to live, every second of the last 30 years of illness with such mind-blowing obduracy, is a testament to the core of who he was," she told mourners.

Erich Segal was born in New York and was an honorary fellow of Wolfson College at Oxford University.

He is survived by his wife, Karen James, and daughters Francesca, 29, and Miranda, 20.