Both women said that they had been tricked by North Korean agents into thinking that they were participating in a harmless prank for a reality show and that they had no intention of killing Mr. Kim.
Ms. Huong appeared to be crying during much of a court hearing on Monday where she entered her plea. But she left court smiling broadly.
The judge in the case, Azmi Ariffin, told Ms. Huong in court that she was fortunate to escape a death sentence and that she should be grateful to prosecutors and the attorney general, Tommy Thomas, for agreeing to the plea deal.
“You are a very lucky person today, because from the original charge of murder, which carries a mandatory death sentence, the prosecutor has offered a lesser charge of voluntarily causing harm with VX,” he said.
Ms. Huong’s lawyer, Hisham Teh, told reporters that he had argued that she should have been freed sooner, as her co-defendant was, because she was “naïve and gullible and was exploited.”