KUALA LUMPUR (Jan 27): Saudi Arabia said it would investigate claims that Prime Minister Datuk Seri Najib Razak had returned to the Saudi royal family US$620 million from the US$681 million (RM2.6 billion) that was channelled into his private bank accounts in 2013, The Sydney Morning Herald reports.

The daily, however, reported that a spokesman for the Saudi Foreign Ministry refused to comment further on the matter.

Yesterday, Attorney-General Tan Sri Mohamed Apandi Ali said there was insufficient evidence to implicate Najib of any offence in receiving the money.

Najib had said the money came from Saudi Arabia to help his ruling coalition's election campaign in 2013.

Riyadh has largely stayed silent over the issue, which was first revealed by The Wall Street Journal in July last year.

"Evidence obtained from the investigation does not show that the donation was given as an inducement or reward for doing or forbearing to do anything in relation to his capacity as a prime minister," Apandi told a press conference yesterday.

"Furthermore, in August 2013, a sum of US$620 million (RM2.03 billion) was returned by the PM to the Saudi royal family because the sum was not utilised."

BBC today quoted an unnamed Saudi source who confirmed the kingdom donated the RM2.6 billion to Najib, saying it was to counter influence from Egypt's Muslim Brotherhood, in what is seen as targeted to ensure Islamist party PAS did not win the 2013 polls.

At the time of the donation, the Saudis were already upset at events in Egypt, where then President Mohammed Morsi was busy consolidating the Brotherhood's hold on the country.

"It would be another three months before Morsi was to be deposed by the army, and the Saudis were convinced that the opposition was being supported by the Brotherhood and Qatar, which backed the Brotherhood and other Islamist groups in the Middle East," the BBC report added.

The report also quoted a British corporate investigator with extensive experience of the Middle East as saying that the US$681 million was paid through the Singapore branch of a Swiss bank owned by the rulers of Abu Dhabi.

"It is very murky", he said.

"This case will never be fully cleared up until the Saudis and the Malaysians release all the transaction data, and that has not happened."

Meanwhile, the Malaysian Anti-Corruption Commission said it was seeking a review of Apandi's decision, and would present its investigation papers on Najib to the operations review panel, which monitors the anti-graft agency.