The Queen considered the Prince of Wales as a future governor-general of Australia – but only once he was married, archive documents have suggested.

Charles was rumoured to have been in the running to become the Queen’s representative in the Commonwealth country during the mid 1970s.

The speculation in the press even reached the prince, then a Royal Navy officer, who said in a interview if there was interest in him taking up the role he would be “delighted to consider it”.

Newly-released correspondence between Australia’s then governor-general Sir John Kerr and Sir Martin Charteris, the Queen’s private secretary at the time, revealed the idea was taken seriously.

Sir Martin, writing in August 1976, told the Queen’s representative: “I think the point we must all bear in mind is that I do not believe the Queen would look with favour on Prince Charles becoming governor-general of Australia until such time as he has a settled married life.”

The private secretary said in his letter to Sir John, who re-married in 1975 after the death of his first wife the previous year: “No one will know better than you how important it is for a governor-general to have a lady by his side for the performance of his duties.

“The prospect, therefore, of the Prince of Wales becoming governor-general of Australia must remain in the unforeseeable future.”

The correspondence is part of hundreds of documents released by the Australian National Archive following a court ruling.

They shed light one one of the most controversial moments in the country’s political history, Sir John’s dismissal of prime minister Gough Whitlam in 1975, and reveal the governor-general acted “without informing the Palace in advance”.

Then a young naval officer, Charles had only made a few visits to Australia but as a schoolboy had spent two terms as an exchange student at Timbertop, a remote outpost of the Geelong Church of England Grammar School in Melbourne, Australia.

During a 1974 visit to Australia, the prince was interviewed and in the transcript, part of the released papers, said: “I mean I’ve seen in the papers that people say that the reason for me being here this time is a: to look for a property and b: to discuss becoming governor-general.

“But it is not the kind of thing that I can discuss becoming a governor-general, it’s a matter for the Prime Minister to recommend to the Queen.”

Pressed on whether he would “look favourably“ on being suggested for the role, he replied: “… It’s obviously too soon to, you know, consider it really.

“I mean I’m still in the Navy and everything else, but I dare say if there was a, you know, a particular desire for it, I’d be only too delighted to consider it, certainly.”