UK-based mining giant Anglo American says it has been approached by larger rival BHP about a potential multi-billion dollar takeover offer.

Anglo American told the BBC that the proposal is currently being reviewed by its board of directors but did not reveal the value of the offer.

BHP did not immediately respond to a request for comment from the BBC.

If the deal goes ahead it would be one of the mining industry’s biggest mergers in years.

Anglo American – which operates mines in countries like Chile, South Africa, Brazil and Australia – has a stock market value of around £29bn.

Australian-based BHP is the world’s largest publicly listed mining company with a market valuation of about A$229bn ($149bn; £119.5bn).

The move comes a year after BHP bought copper producer Oz Minerals for A$9.6bn ($6.2bn; £5bn).

If finalised, the deal would increase BHP’s access to copper, through Anglo American’s operations in South America.

The price of copper has risen on the global markets by more than 15% this year.

Prices have jumped due to the metal being in high demand as the shift to clean energy accelerates.

“Anglo American’s existing footprint in the copper industry is ultimately what lured a mining giant such as BHP,” Tim Waterer, chief market analyst at financial services firm KCM Trade told the BBC.

Anglo American’s share price has fallen by almost 10% in the last year, which could have helped make it an even more attractive takeover target, Mr Waterer added.

Susannah Streeter from investment platform Hargreaves Lansdown said BHP’s takeover plan “will send a fresh chill through the City of London.”

“There are concerns that if the deal goes through it could be the tip of the iceberg and more giants could leave the exchange.”

BHP’s proposal makes any offer conditional on Anglo American giving up its stake in platinum and iron ore operations in South Africa.

Under the UK’s merger and acquisition rules, BHP has until the close of business on 22 May to make a formal offer for Anglo American.