The colourful host vowed to sue ARN on Wednesday after it tore up his $100 million contract and axed the long-running Kyle and Jackie O Show.
The show has been a ratings juggernaut on Sydney radio for more than 20 years but has struggled to expand its reach into Melbourne and Brisbane.
Sandilands vowed to fight ARN, the parent company of KIIS FM, over the decision to end his contract.
"I don't accept it," he said in a statement.
"My lawyers told them last week this would be invalid. And guess what? It is."
The series-ending move followed a "blue on air" with co-host Jackie "O" Henderson, something that happened "a hundred times in 25 years", Sandilands said.
"ARN took the situation and decided to try and burn the place down," he said.
"They wouldn't even let me pick up the phone to call her or anyone else on the show.
"Then - and this is the bit that gets me - once they'd made it impossible for the show to go on, they turn around and say, 'You didn't fix it. You're fired!'"
ARN announced Sandilands' contract termination on Wednesday morning in a statement to the ASX.
Shares in the company, which also operates the GOLD and iHeart brands in Australia, dipped 1.5 per cent to 33.5 cents inside the first hour of trade.
Prices have fallen 64 per cent since the 10-year deal was signed in November 2023.
ARN suspended the radio host on March 3 and issued him with a breach notice for serious misconduct after he berated Henderson on-air nearly two weeks earlier.
Sandilands denied he breached his contract.Â
ARN said Henderson gave notice she could no longer work with her co-host, triggering an early March decision to terminate her similarly lucrative agreement.
The friction stemmed from Sandilands slamming his broadcast partner for looking into Andrew Mountbatten-Windsor's horoscope.
"You're off with the fairies ... every segment, every time you've spoken, you don't even know what's going on," Sandilands said to Henderson during the broadcast.
He said on Wednesday he apologised to his co-host of two decades immediately after the blow-up and had since offered to continue working with Henderson or another presenter.
"(ARN) weren't interested. They didn't want to fix this," Sandilands said.
"They thought they saw a chance to get out of the contract they signed with me a year ago and they ran with it."
The Sydney ratings darlings are in the second year of a decade-long, $200 million contract which coincided with a poorly received entry into the Melbourne radio market.
The show was hit with repeated decency breaches on Monday after the regulator found ARN had lost control of its content.
Sandilands said ARN knew exactly what it was getting when it signed the deal, adding the network was happy to pay because the show delivered.
"I held up my end. I always have," he said.