The announcement follows the sudden resignation of former leader and deputy leader, Troy Grant and Adrian Piccoli, in the wake of a disastrous campaign in the Orange by-election.

It’s quite a rise for Mr Barilaro, a man who until a little more than five years ago was working on his door-and-window installation business in Queanbeyan, outside Canberra.

Mr Barilaro won his way onto the front bench in 2014. As the Minister for Skills and Training, Mr Barilaro has been the public face of the state government's highly controversial plan to admit more private companies into the TAFE sector

New leadership often results in a cabinet reshuffle, but the preference is understood to be for Mr Barilaro to be installed with minimal or no changes to cabinet before a considered reshuffle in early 2017.

NSW Premier Mike Baird would be part of any new ministry decisions, and government sources say it is unlikely to spark a full cabinet reshuffle before Christmas.

Mr Grant was expected to face a leadership spill in this morning's meeting, but stood down instead, to give the government a chance to “pause and reset”.

Mr Grant’s leadership had been under enormous pressure after the Orange by-election, which saw a record 34 per cent swing against the Nationals candidate on the primary vote.

With some postal votes still to be counted, on Monday night the Shooters, Fishers and Farmers Party candidate Phil Donato held a lead of just 204 votes over the Nationals’ Scott Barrett.