Seasoned diplomat Pablo Kang has been asked to "explore all avenues to progress the case" of the 2024 deaths of Holly Morton-Bowles and Bianca Jones in Laos.
The 19-year-olds from Melbourne's Bayside were backpacking through the southeast Asian nation in late 2024 when they were fatally poisoned with methanol while drinking at Nana Backpackers Hostel in Vang Vieng.
At least six foreigners died during the mass poisoning event, including British woman Simone White, a US tourist and two young Danish women.
The Morton-Bowles and Jones families were outraged this week after it emerged 10 people connected to the methanol poisoning faced court in January and were fined just $185 for destroying evidence.
No charges have been laid over the deaths.
Foreign Minister Penny Wong announced Mr Kang's appointment on Thursday after the Department of Foreign Affairs and Trade apologised earlier this week for not providing more information to the victims' families.
"Since their November 2024 deaths, the Albanese Government has been clear to the Lao authorities of the need for transparency and accountability," Senator Wong said.
"We have consistently conveyed our expectations that charges should reflect the seriousness of the tragedy that killed Holly, Bianca and four other foreign nationals."
Mr Kang is the head of the Southeast Asia regional and mainland division of the Department of Foreign Affairs and Trade and will leave for Laos as soon as possible.
He has previously served as Australia's representative in Cambodia, the United Arab Emirates and Vanuatu.
Ms Morton-Bowles' father, Shaun Bowles, said Australians considering travelling to Laos should rethink their plans and avoid the country.
Opposition Leader Sussan Ley called for Prime Minister Anthony Albanese to summon the Laotian ambassador for a "formal explanation" on Tuesday about the "weak prosecutions".
In question time, Mr Albanese acknowledged the court developments had "added to the heartbreak" of the families.
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