Channel Nine is refusing to screen a Greenpeace advertisement attacking Coca-Cola over the drink company's opposition to a container recycling scheme.
Greenpeace communications manager James Lorenz says he thinks Nine's commercial ties to Coca-Cola are behind the decision to ban the advertisement from its network.
"All signs point to that, and I just don't see any other reasonable explanation," Mr Lorenz said.
Environmental groups including Greenpeace have waged a high-profile campaign against Coca-Cola Amatil for the drink giant's opposition to a national paid recycling scheme.
Some groups have protested outside Coke's corporate meetings, sent empty cans in the mail to the company's Australian headquarters, or marked Coke vending machines as out of order.
Last week Greenpeace released an advertisement online that showed young people drinking Coke on a beach, before dead birds begin to fall from the sky.
The message is that plastic bottles are killing sea birds and Coca-Cola is fighting legislation that would help solve the problem, Greenpeace says.
Greenpeace intended to have the advertisement screen on Channel Nine during a Friday night football match to try to grab the attention of NSW Premier Barry O'Farrell.
Although Nine initially agreed to screen the advertisement for $22,000, on Thursday it said the deal was off.
"On reviewing the content we deemed it to be offensive to our viewers," Nine's sales director Peter Wiltshire said.
The network did not respond to questions about whether their commercial ties to Coke played a role in their decision.
Mr Lorenz said nothing in the advertisement was overly graphic or sexual, and the reason Nine gave for dropping the ad was "suspicious".
In March Coca-Cola successfully fought laws in the Northern Territory that would have seen a 10-cent refund given to customers who returned containers to approved depots.
The Northern Territory is expected to try to reintroduce the laws after other states and territories recently showed support for the NT's scheme.
But some states are yet to commit to agreement on a national recycling scheme.
South Australia has run its own scheme for decades.
Coca-Cola did not immediately return calls seeking comment.