The two women accused of smearing a deadly nerve poison on Kim Jong-nam, the half-brother of North Korean dictator Kim Jong-un, have been charged with his murder after arriving at court under heavy protection.

Kim Jong-nam collapsed and died shortly after he was attacked with the deadly toxin VX nerve agent in Kuala Lumpur airport on February 13.

Both of the women who have been charged - Indonesian Siti Aisyah and Vietnamese national Doan Thi Huon - reportedly said they believed they were taking part in a harmless prank for a TV show.

Aisyah told police she was paid £73.

Indonesian Siti Aisyah arrives at court. Credit: AP

Malaysian prosecutor Mohamed Apandi Ali said both women would face a mandatory death sentence if convicted.

Two other suspects have been arrested - a Malaysian who is out on bail and a North Korean who remains in custody. Prosecutors said they have not yet decided to press charges on either.

Vietnamese national Doan Thi Huong arrives at court. Credit: AP

Malaysian police say they are also hunting a further seven North Korean suspects, four of whom are believed to have fled back to North Korea on the day of the attack.

South Korea says that four of the key North Korean suspects are thought to be from the country's spy organisation, suggesting that the killing was state-sponsored.

Police believe the North Korean plotters obtained the nerve agent and passed it to the two women who then sprayed it onto Kim Jong-Nam's face as he made his way through the airport. He collapsed shortly afterwards and died on his way to hospital.

Kim Jong-nam was caught on camera reporting the attack.

Kim Jong-nam shares a father with the current North Korean leader Kim Jong-un, who is the young of the two.

He was originally thought to be the heir apparent to the despotic regime but seemingly fell out of favour after he showed dissident tendencies.

The North Korean leadership said Malaysia is attempting to politicise the death of Kim Jong-nam.

On Wednesday North Korea sent a high-level delegation to Malaysia to seek the return of the body and the release of a North Korean arrested in the case.