Former prime minister Paul Keating says the NSW government should resist permitting higher buildings at Barangaroo Central to fund the new underground railway station there, because it will undermine the original concept for descending heights towards the headland park, Barangaroo Reserve.

Mr Keating has been one of the driving forces for a naturalistic park at the tip of Barangaroo that would act as a " pivot point" between the old wharves at Walsh Bay and the new development at South and Central Barangaroo.

There is still pressure to allow greater height and floor space in Central Barangaroo. Credit:Brendan Esposito

But plans to step down the building heights along the huge development site from south to north are now under a cloud.