Mining giant BHP Billiton has put its US-based Fayetteville shale gas assets up for sale, amid pressure from key investors to maximise profits.
The Arkansas field "is currently under review and we are considering all options including divestment", said the world's largest miner in a nine-month operational review. The assets were valued at $919m (£717m) at the end of 2016, according to its annual accounts.
The move comes after BHP rejected calls from activist fund Elliott Advisors earlier this month to end to its 16-year-old dual listing in London and Sydney and the spin-off off its US petroleum business, accounting for 30% of profits in 2016.
Elliott, which has a 4.1% stake in BHP's London listing, wants the Anglo-Australian miner to move to a more tax-efficient structure and make bigger returns to shareholders, arguing it has underperformed peers by around 20% over the last two years.
However, in a statement in the review BHP Billiton chief executive Andrew Mackenzie said: "Everything we do at BHP Billiton is designed to create value for all of our shareholders, today and for the long term. But we have more to do and we are not standing still."
Mackenzie added a simpler portfolio of assets "allows us to improve safety and operational performance more quickly".
BHP first tried to sell the Fayetteville assets more than two years ago, having made the shale gas investment in 2011 before writing it down by $2.8bn a year later after gas prices dropped.
But it shelved the idea of a sale in 2015, saying at the time it planned to "maximize value" of the assets.
However, the miner said the sale of the aluminum and other non-core operations over recent years has generated $7bn is sales and cut the number of assets in its portfolio by over a third.
As regards petroleum, BHP has long said it intends to focus on liquid products in the US, a more lucrative business than dry gas.