The Victorian Government says it will take court action if a huge advertisement near Melbourne Airport, which shows two animals in a compromising position, is not removed.
The , with the slogan, "Rooting for the Wallabies", and can be seen by landing passengers.
The company has been told to remove the ad after painting it on Parks Victoria land without permission.
Parks Victoria says it is unlikely the ad will be removed before next Tuesday.
Planning Minister Matthew Guy says the company can not stall any longer.
"It's more than dragging its feet, it's seeking attention, and it's got that attention," he said.
"At the end of the day I don't expect international visitors to see that image when they're coming into this city, and I'd expect it to be removed as soon as possible.
"If they don't expect that, or don't want it to be the case, then we'll take court action.
"I want it removed.
"It's not appropriate. It is not the kind of advertisement we want for people coming into Melbourne, Australia's most sophisticated city."