Nationals senator Matt Canavan has rounded on his friend and soon-to-be former colleague Barnaby Joyce for claiming to be the architect of the Coalition’s decision to abandon any commitment to net zero emissions.

With Joyce expected to announce within days he is defecting to One Nation, Canavan – who initiated the internal party review that led to the dumping of the policy – effectively accused Joyce of hypocrisy by pointing out it was he as Nationals leader who signed the party up to net zero in 2021.