Citizens' Declaration coordinator Khairuddin Abu Hassan has finally managed to lodge a report against 1MDB, with the US' Federal Bureau of Investigation (FBI).

The former Umno man, who was in 2015 detained under the Security Offences (Special Measures) Act 2012 (Sosma) for lodging multiple reports against the state-owned sovereign fund, in the country and overseas, said the FBI report was lodged in New York on May 12.

"While in New York, I wrote a letter to the United States president (Donald Trump) to inform (about) the alleged misdemeanour by Najib, in allegedly abusing government and the people's money," he said in a statement.

Khairuddin had also lodged two other reports - with the office of the Swiss attorney-general in Bern on Apr 7, and another on Feb 26, with the Australian police on ANZ Bank allegedly allowing money laundering in former prime minister Najib Abdul Razak's account, in regards to the RM2.6 billion found in the latter's personal account in Ambank.

ANZ holds a stake in Ambank.

"The purported betrayal by Najib and his associates with regards to 1MDB, resulting in a loss of RM40 billion in the company, cannot be forgiven as it is akin to being traitor to the country.

"Fortunately, after four years, the police and the MACC are now resuming action on the reports made since 2014, following a change in government," he said, adding that he hopes the new Pakatan Harapan-led government under premier Dr Mahathir Mohamad would get to the bottom of the "biggest financial scandal of this decade."

Khairuddin, who recently contested under Amanah ticket for the parliamentary seat of Jasin in Malacca, and lost, also wants Malaysian authorities to probe former inspector-general of police Khalid Abu Bakar and attorney-general Mohamed Apandi Ali for alleged abetment of Najib.

Khairuddin had previously reported on 1MDB in Singapore, Hong Kong, France, Switzerland, United Kingdom before being arrested and placed under Sosma for two months for allegedly sabotaging Malaysia's financial institution.

Earlier this month, he filed an RM8 million suit against his wrongful detention.