Former Wallabies captain David Pocock has no regrets over his northern NSW coal mine protest despite being arrested and formally warned by the Australian Rugby Union after he chained himself to mining equipment.

The ARU issued Pocock with a written warning on Monday after he was charged with eight other protesters at the Maules Creek mine site.

Pocock declined any interviews but said in his Tumblr blog that he had done the right thing.

He questioned the federal government’s climate change policy and its plans to expand the fossil fuel industry.

“While people may not agree with me being arrested, I hope they will see this as an opportunity to further the conversation about climate change and engage more people in helping to shape what is all of our futures,” Pocock wrote.

He said his parents had always encouraged him to have the courage of his convictions, so he decided to take part in the protest at the mine site in the Leard State Forest.

“Until this weekend, I have never participated in non-violent direct action,” he wrote.

“I have always hesitated – concerned about the impact this might have on my career.”

Pocock was chained to a super-digger with local farmer Rick Laird.

He is due to appear at the Narrabri Local Court on January 14 after being charged with entering enclosed land without lawful excuse, remaining on enclosed land without lawful excuse and hindering the working of mining equipment.

“If I ask myself the question, `What would I want people to do to help me if I was in Rick Laird’s position?’ then I know I made the right decision,” Pocock said.

Pocock has returned to training with the Brumbies as his continues his comeback from a second knee reconstruction.

The Brumbies said no further action would be taken against Pocock other than the written warning.