The Berejiklian government is preparing to privatise its remaining stake in WestConnex, with a scoping study into the ownership of the motorway due later this year.

NSW Treasurer Dominic Perrottet said the study would investigate whether the government should retain its stake in the motorway or use the capital to invest in new infrastructure projects.

Work on the Westconnex interchange at Rozelle. Credit:Ben Rushton

The government sold a 51 per cent stake in the Sydney Motorway Corporation, which is building WestConnex, to Transurban for $9.26 billion in September 2018.

Mr Perrottet said the proceeds from any future WestConnex transaction would be used to extend the government’s $97.3 billion infrastructure program.