Four years ago the politician in charge of aviation, Transport Minister Catherine King, refused to allow Emirates to schedule more flights to and from Australia.

This week Ms King declared a “gift” from one of the prime beneficiaries of that decision, Qantas Airways, of the highly sought-after lifetime membership of its Platinum program.

Ms King acknowledged she had received “Qantas lifetime Platinum” status from the national carrier, stating she had “declared this on my register of interests, to ensure full transparency”.

“The Qantas website confirms the only avenue for reaching this is via flights. As a Member of Parliament for over twenty five years, I am required to travel regularly to fulfil both Parliamentary and Ministerial duties,” she said.

Two of Ms King’s ministerial colleagues defended the perk, which will give Ms King high-priority access to flight upgrades, extra luggage allowances and the right to first-class lounges around the world long after she leaves politics.

“Catherine King has appropriately declared it, but it’s a function of how much she travels,” Deputy Prime Minister Richard Marles said on Tuesday morning. “And you would want our transport minister, someone in her position who’s been in the Parliament for a considerable period of time with great experience to be travelling the country and engaging with Australians all over the nation.”

Housing Minister Clare O’Neil said Ms King “has probably been away from her family for a third of the last 25 years” travelling for her job as a minister and an MP representing Ballarat in Victoria.

“The important thing is . . . she made a declaration of it, and she’s been transparent about it,” Ms O’Neil said.

Qantas did not immediately respond to a request for comment, although the airline was quoted in other media outlets stating the membership was earned through travel.

Qualifying for lifetime Platinum membership requires 75,000 Qantas status points. They could be earned through 375 return business class flights from Australia to London or a total travel bill of $1 million, the equivalent of $40,000 a year for every year Ms King has been a politician, according to the Point Hacks website.

The Office of shadow transport minister Bridget McKenzie declined to comment while waiting for clarity on whether the membership was a corporate gift or earned through travel.