A number of coal and mining projects with a total value of $14bn could be delayed due to a forest moratorium in Indonesia.
Indonesia has drafted rules for a two-year ban on permits for forest clearing, reports Reuters.
The ban follows a $1bn climate aid deal with Norway aimed at avoiding greenhouse gas emissions from deforestation.
Indonesia Mining Association executive director Priyo Pribadi Soemarno said the ban, if implemented, would make it harder for miners to obtain forest land-use permits and they may risk having their existing forest permits revoked, reports Reuters.
Newmont's Indonesian unit plans to develop the Elang copper reserve in Sumbawa Island, while BHP Billiton has the Maruwai coal project in Kalimantan, and Freeport operates the giant Grasberg copper mine in Papua.
The majority of Indonesia's emissions are caused by the clearing of carbon-rich natural and peatland forests.