The cost of developing Regis Resources’ McPhillamys gold mine near Orange in NSW has risen to around $1 billion, almost double earlier forecasts, casting a long shadow over a project that has already been delayed for several years.

The significant increase in costs could potentially kill the project, one broker warned, just as the price of gold hit a record high on Wednesday and is touted to stay elevated as investors flee to safe-haven assets amid geopolitical upheaval.