More than $1 billion was deposited into Malaysian Prime Minister Najib Razak's account between 2011 and 2013, the Wall Street Journal has reported, citing people familiar with the ongoing investigations.
This is far higher than the fund flows to the prime minister's account identified earlier in connection with the probe into state investment fund 1Mlaysia Development Berhard.
Investigators believe a vast chunk of the $1 billion came from state fund 1MDB, the report said.
In January, Malaysia's Attorney-General Mohamed Apandi cleared Najib of wrongdoing, saying $681m deposited in the prime minister's bank account was entirely legal "personal donation" from the Saudi royal family.
The Saudi royals later clarified that the funds were not personal donation to the prime minister but meant for investment.
BBC had reported Saudi Arabia funded Najib in order to curb the influence of the main political opposition power Pan-Malaysian Islamic Party (PAS), whose founders were influenced by the Muslim Brotherhood.
Swiss authorities probing suspected violation of Swiss laws in the transactions related to 1MDB later found that as much as $4 billion was stolen from the Malaysian state fund.
The probe then widened with French and Singaporean authorities starting investigations into the transactions related to 1MDB.
The latest Journal report says money beyond the $681 million landed in Najib's account in 2011 and 2012.
The prime minister is the head of the state investment vehicle he set up in 2009 to fund development projects. International investigations have revealed that money passed through a complex web of transactions before being deposited in Najib's account.
In response to the latest report 1MDB reiterated that money came from Saudi authorities and that no amount was moved to Najib's personal accounts.
"This has been reiterated by multiple lawful authorities including the Malaysian Anti-Corruption Commission, the Malaysian Attorney General, and various reputable international publications, who have confirmed that these funds came from Saudi Arabia," the fund told Reuters in an email response.