Former federal resources minister Ian Macfarlane has defended his career change to lobbying for mining industry.

Protestors dressed as rats lined up outside the Queensland Resources Council’s annual lunch this week, where Mr Macfarlane formally took up his new role as chief executive from Michael Roche.

The protestors accused the former politician of breaching ministerial ethics.

Ex-ministers are not allowed to become lobbyists for industries related to their former portfolio for 18 months, but Mr Macfarlane has only been out of the federal cabinet since September 2015, and did not officially retire until February this year.

 He defended himself against the conflict of interest claim, saying he was not lobbying for any particular company.

“I don't take legal advice from people in rat suits, and I certainly don't believe that there is any conflict with the code of practice,” he said.

“In fact I have checked and I am totally compliant with the code of conduct for ex-ministers.

“The code is managed by the Prime Minister's office and that's where I sought my advice.”

Mr Macfarlane said his contacts — including political ones — would be useful in his new role.

“I'm open to using all the connections I have,” he said.

“In my phone I have 4,370-something contacts, and that's been built over a lifetime in agripolitics and politics.

“My way of operating is to talk to people quietly and sensibly, rather than go out an attack them in public.”

On other matters, Macfarlane responded to reports that green groups may soon lose their charity status for pushing donations into political activism.

“Activists are not conservationists,” he said.

“They're not out there chipping out lantana and clearing weeds from waterways. They're involved in the political fray.

“The fair and transparent thing is for them to have the same [donation] rules as politicians.”