Norway’s $1tn sovereign wealth fund could be forced to dump shares in miners BHP Group and Glencore under new plans to tighten restrictions on coal investments.

The Norwegian government proposed on Friday tightening the rules on coal after intense public pressure over the fund owning stakes in some of the world’s biggest producers of the highly polluting fossil fuel.

Under the proposals, which still need to be approved by the country’s parliament, the Norwegian oil fund would be forced to sell out of any company that mines more than 20m tonnes or uses 10,000MW of coal in power production.

That would capture both BHP and Glencore, as well as German utility company RWE. The fund is a top 10 shareholder in both miners.

Currently, the fund is banned from investing in companies that derive more than 30 per cent of their revenues or activity from coal but can stay invested if the business has plans to bring it under the threshold. It is not clear if the same exception will apply to the new proposal.