Dr Mahathir Mohamad has warned if Umno needed RM2.6 billion to contest the general election, the party might have violated election laws.
"The expenditure statement for each candidate must be reported to the authorities. It is an offence to spend more than a certain amount.
"I apologise if this rule had already been abolished. It was designed to prevent corruption," he wrote on his blog today.
Under the Election Offences Act 1954, the spending cap for candidates is limited to RM200,000 for Parliament seats and RM100,000 for state seats.
As there are 222 Parliamentary seats and 505 state seats contested in 2013, the maximum BN could legally spend on its election campaign was RM95 million.
'I won five times, frugally'
Mahathir said that during his 22-year tenure as Umno president, little money was used, particularly from the party headquarters.
"In fact, BN never won with less that a two-thirds majority in Parliament," said Mahathir.
BN strategic communications director Abdul Rahman Dahlan had recently suggested that Najib is allowed under the party constitution to hold party assets as a trustee.
He said there was no need to reveal the source of funds as Umno has no legal requirement to name its donors.
On July 3, the Wall Street Journal reported that Malaysian investigators have traced nearly US$700 (RM2.6 billion) to Najib's personal bank accounts.
Najib has not denied this, instead stating he did not take 1MDB money for "personal gain".
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