Malaysia has rejected a call to release a Vietnamese woman accused of assassinating Kim Jong-nam, the half brother of North Korean leader Kim Jong-un.

According to Malaysian and international news media on Thursday, Doan Thi Huong will continue to stand trial after Malaysian prosecutors rejected a request from Vietnam to free her and drop her indictment.

Lead prosecutor Muhammad Iskandar Ahmad confirmed that the prosecution received an order to proceed with the case.

The Vietnamese government requested Huong be released after an accused coconspirator in the Kim Jong-nam case, an Indonesian woman by the name of Siti Aisyah, was released on Monday.

Malaysian prosecutors did not provide explanation for refusing to withdraw charges against the Vietnamese woman.

A lawyer for Huong said it is not fair that she remains on trial while the Indonesian defendant who was being tried on the same charges was released. 

The lawyer said Huong was not physically and mentally well enough to continue with the trial and requested to adjourn proceedings.