The United States formally concluded Tuesday that North Korea murdered Kim Jong Un's half-brother with the banned VX nerve agent in February last year, blasting Pyongyang for deploying a chemical weapon in a packed international airport.
Kim Jong Nam died shortly after two women, an Indonesian and a Vietnamese national, sprayed his face with a liquid as he walked through Kuala Lumpur airport.
The two women are currently on trial in Malaysia where they are accused of using a nerve agent to murder Kim Jong Nam, who lived in exile in China and was seen as a potential rival to his younger half-brother.
The two women say they were recruited to take part in what they thought were prank TV shows but were instead tricked into becoming inadvertent assassins, in an elaborate plot by a group of North Korean agents who then fled country.
On Tuesday, Washington announced it had formally concluded that VX -- an extremely powerful nerve agent -- was used to conduct the slaying and that North Korea was to blame.
"The Government of North Korea used the chemical warfare agent VX to assassinate Kim Jong Nam, in the Kuala Lumpur airport," State Department spokeswoman Heather Nauert said in a statement.
"This public display of contempt for universal norms against chemical weapons use further demonstrates the reckless nature of North Korea and underscores that we cannot afford to tolerate a North Korean WMD program of any kind," she added.
The statement gave no details or evidence on how the US had come to their conclusion.
The finding triggered another layer of US economic sanctions against Pyongyang, just as South Korea reported that the regime is ready for talks to end a nuclear standoff.
But South Korean President Moon Jae-in sounded a note of caution Wednesday over the North's offer of denuclearization talks, saying it was "too early to be optimistic.”
President Donald Trump welcomed Pyongyang's breakthrough declaration -- as relayed by Seoul -- that it wanted to talk to the US and would not need nuclear weapons if its security was guaranteed as positive and apparently sincere.
It followed months of tensions, threats and personal insults between him and the North's leader Kim Jong Un.
Moon and Kim will sit down for a summit on the southern side of the Demilitarized Zone next month, Seoul said after its envoys returned from a historic trip to Pyongyang.
