The US has announced new sanctions on North Korea after finding Pyongyang deployed a banned chemical agent to assassinate leader Kim Jong-un’s half brother.

“The Government of North Korea used the chemical warfare agent VX to assassinate Kim Jong Nam, in the Kuala Lumpur airport”, the State Department said in a statement.

“The United States strongly condemns the use of chemical weapons to conduct an assassination”, a spokesman added, saying the North Korean regime had shown “contempt for universal norms against chemical weapons”.

Kim Jong-nam died last year after two women attacked him at Kuala Lumpur’s airport, leading Malaysian authorities to charge the alleged assailants with murder, which they deny.

The UN has imposed multiple rounds of sanctions on Pyongyang after a series of nuclear and intercontinental ballistic missile tests, but the State Department’s announcement of new penalties came as the Trump administration eyed a rare diplomatic opening.

After North Korea used the Winter Olympics to make an overture to Seoul, leading to a rare meeting in Pyongyang between officials from the estranged nations, South Korea said the North had expressed a willingness to talk with the US about renouncing its nuclear weapons.

Donald Trump welcomed the new developments on the peninsula as “very positive” and said “we have come, certainly, a long way”.

North Korea indicates it could give up nuclear weapons, according to the South