Indonesian Siti Aisyah, 25, and Doan Thi Huong, 28, a Vietnamese, are charged with killing Kim Jong Nam by smearing his face with VX, a chemical poison banned by the United Nations, at Kuala Lumpur's global airport on February 13.
Raja also confirmed that he found VX on Kim's face, eyes, clothing and in his blood and urine.
"I found VX nerve agent precursors on a "LOL" shirt's sleeve and Siti's sleeve", he said during the examination-in-chief by deputy public prosecutor Wan Shaharudin Wan Ladin.
"The presence of VX precursors and VX degradation products confirms the presence of VX itself", he told the court.
Doan, a Vietnamese national, and Siti, an Indonesian national, pleaded not guilty to murdering Kim on Monday, in proceedings which have seen their defense claim that the two were participating in what they believed was a TV prank show.
He explained that the VX nerve agent would cause complications leading to respiratory failure and could cause death.
North Korea is planning to test a missile that its officials said could be capable of reaching the U.S. West Coast, according to two Russian legislators who returned from a visit to Pyongyang this week.
VX nerve gas is known to be most toxic among chemical warfare substances. "If the decontamination process was carried out within 15 minutes of being in contact with VX, it would not cause a fatality", he added.More news: US Army special forces soldiers die in ambush in Niger
"It is very hard to detect as it is (an) odourless, colourless and tasteless oily liquid in its pure form".
She agreed that a person with VX on the hands may not be fully decontaminated by washing it off with soap and water.
"We need the devices to detect VX nerve agent", he said, when Wan Shaharudin asked if airports in Malaysia had the devices to detect VX nerve agent. As per my knowledge, there are no detectors in Malaysian airports to trace VX.
"There's a clarity of goal in what Kim Jong Un has done", CNN news quoted Yong Suk Lee, deputy assistant director of the CIA's Korea Mission Center, who discussed the escalating tensions between North Korea and the United States during a conference organised by the agency at George Washington University.
North Korea has a history of ordering killings of people it views as threats to its regime and its chemical weapons arsenal is believed to include VX. All three countries remain at war today and North Korea has cited the latter two as examples of governments that canceled their nuclear programs only to be later attacked by the U.S.
The testimony Thursday was the first evidence linking VX to either of the two suspects.
The Frontline film assumes that this was the work of the North Korean intelligence assets at the behest of Kim Jong-Un, who already held full power in Pyongyang. If convicted, they could face the death penalty. Many pledged to investigate, others said they already cut ties with some suppliers.
He also said Subramaniam was inconsistent and shouldn't be afraid to open the VX-tainted samples since he testified VX could easily be washed off and doesn't evaporate quickly.