Austrac investigates banks, casinos and betting companies to make sure they have robust compliance systems to prevent them from profiting from the proceeds of crime.

Ladbrokes owner Entain has also been probed in Australia since 2022, while another rival Sportsbet is facing an external audit.

Under Australian law, firms are required to assess customers and monitor their financial transactions in order to identify, mitigate and manage the risk that they might be engaging in money laundering or financing terrorism.

Any companies found by Austrac to have weak compliance systems could be fined.

In recent years the watchdog has hit major lenders Westpac and Commonwealth Bank of Australia with large fines for breaches of the anti-money laundering and counter-terrorism financing laws.

The online betting industry also faces other challenges in Australia such as new laws banning the use of credit cards for online gambling and stricter federal government rules on adverts.

Last year, Bet365 reported a significant loss but its chief executive Denise Coates was paid around £221m.

That was £7m higher than the previous year and Ms Coates also received at least £50m worth of dividends.

The pay bump means that her total salary over the past four years surpassed £1bn.

Ms Coates founded the Bet365 website in a portable building in a Stoke-on-Trent car park more than 20 years ago.

She is thought to be one of Britain’s richest women and among the best-paid executives in the world.