Saudi Aramco has named three major banks to its international advisory team as it prepares for what could be the biggest initial public offering in history, according to a Reuters report, with JPMorgan (JPM) - Get Report , Morgan Stanley (MS) - Get Report and HSBC (HSBC) - Get Report surviving the final cut.

The report, published Thursday, follows a string of events that suggest the state-owned oil company is edging closer to the planned sale of around 5% of its overall value, a listing that would give the world's biggest oil company a market capitalisation of as much as $2 trillion. Reuters also said that Moelis & Co. and Evercore Partners had been appointed as financial advisers for the share sale, alongside Saudi-based NCB Capital and Samba Capital.

Earlier this week, Saudi Arabia slashed Aramco's corporate tax rate to 50% from 85%, a move some analysts have said could lift the company's IPO value by around $400 million.

"This Royal Order on tax for oil and hydrocarbon producers operating in the Kingdom brings the Kingdom of Saudi Arabia in line with international benchmarks," said Saudi Arabia's Energy Minister Khalid Al-Falih in a statement. "It is very important to make it clear that the hydrocarbon resources of the Kingdom of Saudi Arabia remain sovereign and that any reduction in tax revenues arising from this Royal Order is replaced by stable dividend payments and other sources of revenue from hydrocarbon producers to the government."

Aramco hasn't said where is intends to list, and exchange operators have been salivating at the idea of hosting what will immediately become the world's biggest corporation. That said, the Kingdom is likely to opt for multiple listings on various global platforms, including Riyadh, alongside the NYSE or the London Stock Exchange. 

Saudi Aramco is one of the largest oil exploring and producing companies in the world. It is nearly as big as Venezuela's oil reserves as a whole, larger than Canada's oil reserves and several times greater than its other global corporate competitors such as BP (BP) - Get Report ExxonMobil XOM, PetroChina, and Rosneft.

Saudi Aramco boasts crude oil and condensate reserves of nearly 260 billion barrels and nearly 294 trillion standard cubic feet of natural-gas reserves. Reports suggest that Saudi Arabia was the world's second-largest producer of crude oil and natural-gas liquids in 2014, with a production of 11.6 million barrels per day. Read Everything You Need to Know About the Aramco IPO.