Angola's prosecutor general on Monday vowed to use "all possible" means to bring back Isabel dos Santos, the ex-president's billionaire daughter who is accused of siphoning off millions of dollars of public money.

"We will use all possible means and activate international mechanisms to bring Isabel dos Santos back to the country," prosecutor general Helder Pitra Gros told public radio.

Dos Santos left Luanda after her father's successor President Joao Lourenco came to power in 2017, and now moves mostly between Lisbon and London.

The prosecutor's remarks came after a trove of 715,000 files dubbed the "Luanda Leaks" was released at the weekend and accused the eldest daughter of former president Jose Eduardo dos Santos of funneling state funds from the oil-rich country into overseas assets.

Authorities in Angola have compiled a list of at least 10 Maltese companies they believe the billionaire daughter of a former African dictator may have used to siphon money out of state enterprises.

Isabel dos Santos and her husband Sindika Dokolo used local financial service practitioners, including a former MP, to set up the letterbox companies, some of which were given Angolan state contracts and funds.  

Back home, the 46-year-old Dos Santos is already being probed under an anti-graft campaign launched by Lourenco, who has vowed to root out corruption and rebuild the economy.

Prosecutors last month froze the bank accounts and holdings owned by the businesswoman and her Congolese husband Sindika Dokolo.

The prosecutor general said "it was quite a coincidence that she received our (investigation) notification during the day and at night she left the country".

He did not specify when exactly she left the country. "We have asked for international support from Portugal, Dubai, and other countries," he said.

Dos Santos has denied any wrongdoing and denounced the investigation as "politically motivated."