The investigation into the death of the exiled half-brother of North Korea's ruler Kim Jong Un is being carried out in an impartial manner, Malaysia's ambassador to Pyongyang has said.
Mohamad Nizan Mohamad, speaking in China's capital Beijing, rejected accusations from the North that the probe was politically tinged.
Mr Mohamad was on his way to Malaysia after being recalled following the death of Kim Jong Nam last week.
Mr Kim appeared to have been poisoned at Kuala Lumpur's international airport and police have so far arrested four people carrying identity documents from North Korea, Malaysia, Indonesia and Vietnam.
The arrested suspects include two women allegedly seen approaching Mr Kim on February 13 as he stood at a ticket kiosk at the airport's budget terminal.
On Monday, Kang Chol, North Korea's ambassador to Malaysia, attacked the country's investigation into Mr Kim's death, calling it politically motivated and demanding a joint probe.
Malaysia's foreign ministry responded that the ambassador's comments were "culled from delusions, lies and half-truths".
Mr Mohamad said the country's investigators were proceeding in a professional manner and would "be very objective and fair to everybody".
"I think the investigation is still ongoing, so just wait and see for that," he said.
"And we can assure you of the impartiality of the investigation itself because there is no reason for us to be sided with anybody."
The attack took on added political dimensions when Malaysia refused demands by North Korean diplomats to turn over Mr Kim's body and proceeded with at least one post-mortem examination over the diplomats' objections.
Mr Kang told reporters that Malaysia was working in collusion with South Korea as Seoul tries to deflect attention from its own months-long political crisis.
Police "pinned the suspicion on us, and targeted the investigation against us", he said.
He referred to the dead man as "Kim Chol", the name on the passport found with Kim Jong Nam.