Johnson requested an early exit from his contract yesterday after being told by the club recently he was free to look elsewhere, the inference being the club wasn't about to offer him a new deal when his current contract expires at the end of next season.
Johnson has played his entire professional career with the Warriors making his NRL debut with the club in 2011.
The situation escalated when the 162-game veteran Johnson returned home from the Kiwis tour of England, pronouncing unhappiness this week that the club he has served since 2011 had made no offer for 2020 and beyond.
The 28-year-old said he had "spread his wings" and was assessing options elsewhere.
Warriors CEO Cameron George said the release was effective immediately.
"Yesterday (head coach) Stephen Kearney, (recruitment manager) Peter O'Sullivan and I met with Shaun and his manager Peter Brown," he said.
"During the meeting Shaun clearly demonstrated to us that he didn't want to be at the club in 2019.
"On the basis of what Shaun told us, we are not going to compromise our culture on and off the field with people who do not wish to represent our club, members and fans in the way we expect.
"Everything we do is about the club being first and what's best for our future, our development and ultimately our results.
"While it's disappointing it has come to this, we must acknowledge the contribution Shaun has made to the Vodafone Warriors. We're proud of what he has achieved at the club and wish him the best for the future."
Cronulla and Parramatta are possible destinations for the 29-Test Kiwis star while St George Illawarra can't be discounted after news emerged overnight the Dragons' English playmaker Gareth Widdop is seeking a release.