The Australian mining company whose executives have been detained in Africa over a tax dispute have agreed to pay $US160 million ($242 million) in a bid to free them.

Perth-based Resolute Mining have said they will pay the sum to Mali's government, which is holding three of its executives captive in the nation's capital, including CEO Terry Holohan.

In a statement to the ASX on Monday morning, Resolute said the payment was part of an agreement regarding the miner's operations in Mali.

The miner said last week three of its executives had been "unexpectedly detained" following discussions with mining and tax authorities regarding Resolute's "in-country business practices."

WA's premier last week said the trio had not been harmed and was "being looked after."

Resolute working to secure release

Resolute said Monday's memorandum of understanding, or protocol, provided that all outstanding claims against the company with Mali's government, including those related to tax, customs levies, maintenance and management of offshore accounts, are settled.

Resolute has made an initial payment of $US80 million with a further $US80 million pending in future months "from existing liquidity sources."

Resolute said it was working with the government on the remaining steps to secure the release of Mr Holohan and the two other executives.

"They remain safe and well and continue to receive support on the ground from the UK and International Embassies and Consulates," Resolute said.

Executives in Mali for talks

The executives had travelled to Mali's capital Bamako to hold discussions with mining and tax authorities regarding Resolute's "in-country business practices, and to progress open claims made against Resolute, which the company maintains are unsubstantiated".

Resolute has an 80 per cent stake in the Syama Gold Mine.

It's understood Mr Holohan is a British citizen and while the Department of Foreign Affairs and Trade does not have a consular role in the matter, it was in close contact with other embassies in the region.

Resolute Mining's stocks have plunged in the days after the company publicly confirmed the news.