Western Australian Senator Rod Culleton has resigned from Pauline Hanson's One Nation party, a move welcomed by the party leader who said he was a "pain in the backside" and she was "glad to see the back of him".

Senator Culleton will continue his term as a senator for Western Australia independently of One Nation, according to a media release tweeted from the senator's official Twitter account on Sunday night.

The maverick senator cited a fraught relationship with Senator Hanson, a lack of respect from party colleagues and a slew of policy differences with the One Nation team.

"Policy decisions have been run in morning media, with no consultation, discussion or agreement from the party room and personal attacks and undermining, un-Australian behaviour towards myself and my team, has been ongoing and terms dictated to the team," Senator Culleton said in a statement.