Timber industry owners in Queensland have accused the state-owned forestry enterprise of price gouging, creating the most expensive logs in Australia.

Although already making A$100m a year profit, Forestry Plantations Queensland has increased royalties from 9% to 14% and backdated the increase four months.

The price of logs is now 15% higher those paid by New South Wales mills, said the industry body Timber Queensland.

Chief executive Rod McInnes said the government was short of cash and was pushing forestry to get as high a return as possible. “We’ve got to the point where we are not making money.”

Industries minister Tom Mulherin said the forestry monopoly had dealt “productively” with the industry and the owners were leveraging for more government assistance.

“These are the first increases since 2002,” he said, adding that the owners had wanted a 2.8% decrease.

However, Mr McInnes said: “We are being price gouged by a monopoly supplier.”