The iron ore price will go to US$140 per tonne and the copper price will rise to US$8,600 per tonne, according to the upgraded three-month forecast of top broker Citi.
Citi previously predicted the iron ore price would lift to US$120 per tonne and the copper price would go to US$7,500 per tonne.
But now, the broker says fiscal support from the Chinese government to expand its economy and support the ailing property market will be "larger and more imminent than we previously expected".