Abu Dhabi is planning to invest around $1.5 billion to buy shares of Saudi Aramco as the oil giant prepares for its much-awaited initial public offering, according to media reports.

Abu Dhabi will invest in Aramco through one or more of its state-owned entities. However, reportedly, the entities have not been decided yet and the amount to be investment could also change.

In the last few weeks, Aramco has been holding meetings with fund managers and investors across the Middle East for its IPO. According to the reports, the Kuwait Investment Authority (KIA) is also considering an investment of around $1 billion in Aramco’s IPO, which will be the world’s biggest.

Earlier this week, Aramco officials also met with potential investors behind closed doors in Dubai to persuade them to invest in its IPO.

While many investors showed interest in Aramco’s IPO, however, some investors have decided to not buy Aramco’s share. Malaysia’s state-owned oil and gas giant Petronas was the latest to announce its decision to not take part in Aramco’s share sale.

Earlier this month, Aramco, which is the world’s most profitable company, announced its decision to sell 1.5 percent of the company or about 3 billion shares on the Tadawul and raise around $25 billion. Saudi Arabia’s Crown Prince Mohammed Bin Salman was aiming for the coveted $2 trillion valuation for the oil behemoth, but now the kingdom has settled for a valuation somewhere between $1.6 trillion and $1.8 trillion.

Aramco’s IPO is the centerpiece of Crown Prince Mohammed bin Salman’s plans to diversify the Saudi economy and reduce its dependence on oil.

According to media reports, around 3.72 million retail investors had subscribed to 1.017 billion Aramco shares so far.