Parramatta superstar Jarryd Hayne is set to take leave from the NRL after being given a conditional release by the Eels to try his hand at NFL.

Hayne, who has withdrawn from the Kangaroos Four Nations squad announced on Tuesday, told a press conference that he felt the need to "follow his heart" even though he knew there would be "dark days" ahead.

Hayne said the move had been a long time coming, and with the deadline looming, he had decided to take the plunge: "Opportunities come up in life and you need to take them and not live with regret," the emotional star said.

The 27-year-old fullback, who had another year to run on his contract with the Eels recently visited Seattle Seahawks, but said he has no current options with them or any other franchise.

Hayne wil be aiming to join a train-on team for the next 12 months as the rosters are closed for the 2014 NFL season.

In a statement on the Eels website, Hayne said the reason he did not leave earlier was out of loyalty to coach Brad Arthur.

"The reason I didn't make this decision any earlier was because of the part I played in getting Brad to the club and the way we finished the season. I felt I owed the club one more year and I gave it everything I could," he said.

"It's always been a dream of mine to play in the NFL, and at my age, this is my one and only chance at having a crack at playing there.

"I'm excited about the potential opportunities that lie ahead. I've known the deadline has been looming for me to make this call, and I believe the right time is now.

"I'm so passionate about the challenge that lies ahead for me, not only as an athlete but more so as a person. It's the hardest decision I have ever had to make in my life. I'm leaving my teammates, friends, and most importantly my family; but for me to grow as an athlete and a person I feel this is the right step to take.

"It hasn't been an easy decision for me to leave the Eels, the club's been my home and family since I was 13, and I've always been proud to pull on the Blue and Gold jersey with my teammates.

"The hardest thing about leaving the club is there's stability for the first time in a long time, but I know where my heart lies and I'm following that.

"I'm always telling people to chase their dreams and follow their hearts, if I don't live by that I'm not being honest with myself.

"I'm leaving knowing that I have signed a 'lifetime agreement' with the Eels, so if I return to the NRL, it will be to Parramatta."

Eels chairman Steve Sharp said the Eels were devastated to lose their "favourite son", and that the door is always open.