KUALA LUMPUR: 1Malaysia Development Berhad (1MDB) was the tipping stone that caused former prime minister Tun Dr Mahathir to turn against Datuk Seri Najib Tun Razak.
Speaking to reporters after his speech at "My most dangerous idea: A conversation with Tun Dr Mahathir bin Mohamad" at the 2015 Cooler Lumpur Festival in Kuala Lumpur on Saturday, Dr Mahathir said that while there were many things the Prime Minister did that he disagreed with, 1MDB was inexcusable as it concerned vast amounts of money.
"When I found out that money was missing, I just could not support him despite my wish to help him, even though he is the son of the man I idolised who made me prime minister.
"This is the straw that broke the camel's back... This is using billions of Government money. That I cannot accept," he said.
"When you borrow money it is not your wealth. It's the wealth of the bank. That's cheating," said Dr Mahathir, who criticised 1MDB's purchase of power plants and other Government property at inflated prices.
Dr Mahathir said he gave Najib a second chance after he had fared worse in the general election compared to former prime minister Tun Abdullah Ahmad Badawi.
However, he changed his mind once news of 1MDB's dealings broke.
According to Dr Mahathir, Najib appeared to believe that money would make the public love him.
"He seemed to think that if you give money to people, they will love you. So he gave money - RM500 to three or four million people. Spending money that way is wrong. It is Government money," he added.
"I told him it is wrong but he says, 'cash is king'. But I know he was not popular despite giving money to people to have a big gathering where they were provided with a placard saying 'I love PM," said Dr Mahathir.
"You don't go to your girlfriend and ask her to carry a card saying 'I love you'. If people love you they will. They don't have to raise a card. That was the advice I gave him but he didn't follow it," said Dr Mahathir.
In a blog post on najibrazak.com Friday, Najib said the motivation behind Dr Mahathir's attacks was to pressure him to resign, similar to what happened to his immediate predecessor, Tun Abdullah Ahmad Badawi.
Najib also stressed that Dr Mahathir's accusations with regards to 1MDB were false.
He added that because Dr Mahathir was a former head of government, the market and public sentiment had been negatively influenced.
Najib also reminded Dr Mahathir that he had instructed the Auditor-General (A-G) and the Public Accounts Committee (PAC) to scrutinise 1MDB.