Phil Everly dead: World mourns younger of US rock and roll duo The Everly Brothers

Everly died in California following complications from lung disease

This July 31, 1964 file photo shows The Everly Brothers, Don and Phil, performing on stage. Everly, who with his brother Don formed an influential harmony duo that touched the hearts and sparked the imaginations of rock 'n' roll singers for decades, inclu (AP)

The world is mourning US rock and country musician Phil Everly, the younger of The Everly Brothers, who has died in California aged 74.

His wife Patti told The Los Angeles Times her husband had died following complications from lung disease after a lifetime of smoking. "We are absolutely heartbroken," she said. "He fought long and hard."

His son Jason Everly said his father had been in the hospital in Burbank for about two weeks before he passed away.

Everly's last public performance came in 2011, but he had been actively writing music after this, his son added.

Everly and his brother Don had 19 top 40 hits between 1957 and 1962 and a musical career spanning five decades.

Their music influenced the Beatles, the Beach Boys, the Byrds and many other rock, country and folk singers. Their hits included "Cathy's Clown", "Wake Up Little Susie", "Bye Bye Love", "When Will I Be Loved" and "All I Have To Do Is Dream".

The Beatles once referred to themselves as 'the English Everly Brothers' and Dylan, pop culture's poet laureate, once said: "We owe these guys everything. They started it all."

Rolling Stone magazine said their music "merged Nashville's clean instrumental country style with innocuous teenage themes, and were smoother than other contemporary country-rock hybrids like rockabilly".

The duo dramatically broke up onstage at a concert in Knott’s Berry Farm in California amid quarrelling in 1973 before they reunited in 1983, "sealing it with a hug", Phil said.

Two generations later, artists are still finding inspiration in the Everly Brothers. Most recently, Green Day's Billie Joe Armstrong and Norah Jones recorded a tribute to the Everlys and their unique album Songs Our Daddy Taught Us.

"There's so much darkness in those old songs," Armstrong said in an interview. "I think mainly that's just how people communicated when it came to mourning and loss. Then with the Everly Brothers it sounds like these two little angels that sing."

Although their number of hit records declined in the late 1980s, they performed in successful concert tours across the US and Europe.

They were inducted into the Rock 'n' Roll Hall of Fame in 1986, the same year they had a hit pop-country record, "Born Yesterday". The pair were also awarded at lifetime achievement award at the 1997 Grammys.

Don Everly was born in 1937 in Brownie, Kentucky, to Ike and Margaret Everly, who were folk and country music singers. Phil was born two years later in 1939 in Chicago, where the Everly family had relocated to when their father stopped working in the coal mines.

The brothers began singing country music in 1945 on their family's radio show in Shenandoah, Iowa. Their career breakthrough came when they moved to Nashville as teenagers in the mid-1950s and signed a recording contract with New York-based Cadence Records.

The international hit "Bye Bye Love" rocketed the Everly Brothers to fame in 1957.

During their break-up they pursued solo singing careers with little fanfare. Phil also appeared in the Clint Eastwood movie Every Which Way But Loose.

In 1986 Don Everly told The Associated Press the two were successful because "we never followed trends. We did what we liked and followed our instincts. Rock 'n' roll did survive, and we were right about that. Country did survive, and we were right about that. You can mix the two but people said we couldn't".

Phil is survived by his brother Don, his wife Patti, sons Jason and Chris, his mother Margaret and two granddaughters.

Additional reporting by Associated Press