Saudi Arabia has sought to allay fears among investors after an anti-corruption purge that swept up a host of business and political titans, with concerns mounting that the arrests could trigger political instability.

Billionaire tycoon Prince Al-Waleed bin Talal, dubbed Saudi Arabia's Warren Buffett, was among dozens of high-profile figures arrested or sacked at the weekend, in the biggest purge of the kingdom's elite in its modern history.

Authorities have frozen the bank accounts of the accused and warned that assets related to the corruption cases -- potentially worth billions of dollars -- would be seized as state property, as the government appears set to widen the crackdown.

The purge triggered uncertainty among businesses that could lead to capital flight or derail reforms, experts say, at a time when the kingdom is seeking to attract badly needed investments to offset a protracted oil slump.

The central bank stepped in this week to soothe those concerns, insisting that the targets were errant individuals and not entire corporations -- not even those with ties to the arrested businessmen.

"Corporate businesses remain unaffected. It is business as usual for both banks and corporates," the central bank said.

The Saudi Arabian General Investment Authority (SAGIA), whose former chief Amr Dabbagh was reportedly among those arrested, sought to drum up support for the anti-corruption drive, saying it would create "a fair and level playing field for all investors".

"This is a clear sign that the kingdom is ready to protect... investments from legally reprehensible actions," the investment authority said.

- 'Uncertainty' -

Coming just two weeks after a glittering investment summit, which Crown Prince Mohammed bin Salman used as a platform to pledge a "moderate" Saudi Arabia and to showcase his ambitious reform drive, the purge has spooked some businessmen.

Further roiling sentiment are rumours that the venue of the summit, Riyadh's palatial Ritz Carlton hotel, is where many of the arrested elites are being held.

Aside from Prince Al-Waleed, who has extensive multi-billion-dollar investments inside and outside Saudi Arabia, the arrested figures include Waleed al-Ibrahim, owner of the influential Arab satellite network MBC, as well as construction tycoon Bakr Bin Laden and billionaire Saleh Kamal.

Saudi forces have grounded private jets at airports, possibly to prevent high-profile figures from leaving the country, an aviation source said, provoking fears of a widening crackdown.

The anti-graft campaign comes after Saudi Arabia, the world's top oil supplier, posted more than $200 billion in budget deficits over the past three fiscal years due to the energy slump. It is headed for a fourth year of shortfalls.

To fund those deficits, the kingdom has withdrawn around $250 billion from its reserves since the end of 2014 and has borrowed around $100 billion from domestic and international markets.

"The anti-corruption crackdown will inflict short-term pain but can provide long-term gain," said M.R. Raghu, head of research at Kuwait Financial Center.

"It is bound to unnerve foreign investors but some could view this as a positive step which could increase the kingdom's ranking in terms of the ease of doing business," Raghu told AFP.

Prince Mohammed, the architect of the Vision 2030 programme of reforms for a post-oil era, has announced a host of mega projects, including a futuristic megacity with robots and driverless cars, which require hundreds of billions of dollars in investments.

The cornerstone of the kingdom's economic reforms is a planned initial public offering of nearly five percent of giant national oil company Aramco next year.

"In the short-term this (the crackdown) will increase risk premium, reduce liquidity and create uncertainty. However, if this leads to reducing corruption, it can be a huge positive for the economy," Raghu said.

- 'Consolidate power' -

With the purge, which analysts describe as a bold but risky power play that has concerned investors, Prince Mohammed appears to have centralised power to a degree that is unprecedented in recent Saudi history.

"The anti-corruption drive is another sign that Mohammed bin Salman is attempting to consolidate power ahead of a possible abdication by his father, King Salman," said research firm Capital Economics.

The prince has especially sought to consolidate his control over the security services, removing what observers describe as the last vestiges of opposition in his path to the throne.

Among those ousted in the purge was Prince Miteb bin Abdullah, the 64-year-old son of the late king Abdullah, who headed the Saudi Arabian National Guard. The internal security force has long been seen as a locus of tribal power and a stronghold of king Abdullah's family.

Capital Economics said with the anti-graft drive "opposition towards Mohammed bin Salman within the royal family, business elite and religious establishment could build, potentially threatening the reform plans."