The Australian competition watchdog has raised concerns over a proposed plan by Virgin Australia to take control of Tiger Airways.

The deal could reduce competition by eliminating a major and independent player in Australia's domestic air travel market, said the regulator on Thursday. Tiger Airways Australia - an arm of Singapore's Tiger Airways Holdings - is the third biggest carrier Down under, after Qantas and Virgin.

Even as it flags its concerns, the Australian Competition and Consumer Commission said in a statement that it is also mindful that if the deal is blocked, Tiger could exit the market altogether.

Tiger's shareholders have said yes to the tie-up which will see Virgin forking out A$35 million ($44.7 million) for a 60 per cent stake in the budget carrier. The regulator has called for further submissions and will issue a final ruling on March 14, it said.