Papua New Guinea's Prime Minister James Marape is to make his first submission to an inquiry into a controversial state loan today.
The $US1.2 billion loan was used by the Peter O'Neill-led government in 2014 to buy a stake in the company Oil Search, but the value of its share bottomed out.
A Commission of Inquiry is investigating whether the country's leaders broke the law in taking out the loan with Swiss bank UBS.
Last year, an Ombudsman Commission report tabled in Parliament implicated both Mr O'Neill and Mr Marape, who was finance minister at the time.
The inquiry has faced operational constraints and delays, with many high level officials expected to appear.
The head of the commission, former chief justice Sir Salamo Injia, last week warned he wouldn't hesitate to punish people who were delaying the process.