Transurban has sought to dampen expectations it is in the box seat to buy a majority stake in WestConnex from the NSW government, citing the many toll roads it has snapped up from receivers for firesale prices as a sign of its unwillingness to overpay.

The insistence that "no asset is a must have for us" came as Australia's toll road king boosted pre-tax profits from its labyrinth of motorways in Sydney by 10 per cent to $387 million in the first half of the financial year, helped by an increase in truck tolls on the M7 and the Eastern Distributor. Two fifths of Transurban's revenue comes from Sydney.

The government wants the sale of a majority stake in WestConnex completed by the middle of the year. Credit:Ben Rushton

Transurban chief executive Scott Charlton said the company was benefiting from a high volume of trucks on roads due to the construction boom in Sydney.

‘‘We see significant opportunities particularly given the strength of the Sydney and the Melbourne markets on the back of population growth,’’ he said.