The Civil Aviation Administration of Vietnam (CAAV) and Vietnam's Ministry of Transport has told Jetstar Pacific that its use of the Jetstar brand is contrary to aviation law.
The two regulators have "expressed concern regarding Jetstar Pacific's current use of the Jetstar brand," says a Jetstar spokesman in Melbourne, in response to Vietnamese news media reports.
These reports, citing the CAAV, say the authority takes issue with the fact that the domestic Vietnamese carrier is using a foreign brand name.
Jetstar's spokesman says the airline's shareholders - Qantas Airways and Vietnam's State Capital Investment Corporation - are talking to the Vietnamese Government to try and resolve the issue. Jetstar in Australia is Qantas' subsidiary and Qantas owns 27% of Jetstar Pacific.
"The cross-border use of branding is standard international practice and one that already has precedent in Vietnam and in the aviation industry across Asia," says Jetstar.
Jetstar Pacific has been able to achieve an increase in market share and passenger traffic, thanks in part to having the Jetstar brand, it adds.