Research from the firm found that 483 projects globally were under construction or due to begin construction by 2020, with combined capex of US$253 billion.

Capex for projects already in the construction phase accounted for $162 billion.

"The global mining sector has been reeling under declining commodity prices, increasing production costs and declining ore grades, which have negatively impacted investment. However, a turnaround is starting to be seen with APAC leading from the front," GlobalData senior mining analyst Ankita Awasthi said.

The APAC region accounts for 38% of the projects, including the largest, but only 23% of the planned spend.

The Middle East and Africa account for 15% of the projects and 20% of capex, the former Soviet Union 14%, followed by North America with 10%.

Oceania accounts for 18% of the total planned spend, thanks to the largest planned project, Adani Group's $16.5 billion Carmichael coal project in Queensland, followed by North America with 15%, which has the second in Barrick Gold and Novagold's Donlin gold project in Alaska.

Commodities with the greatest spending planned or in progress are coal (24%), gold (19%), copper (18%) and iron ore (9%), which collectively have 240 projects under construction and 80 at the feasibility stage.