The Turnbull government's recently restored parliamentary majority is again under threat with aggrieved Nationals MP Keith Pitt considering joining the crossbench following a ministerial reshuffle in which he and Infrastructure minister Darren Chester were dumped by Barnaby Joyce.

Mr Pitt told colleagues on Tuesday he was considering his options. Publicly, he would only say he would continue to serve his electors in the Bundaberg-based seat of Hinkler, but not in what capacity.