“Gough Whitlam, Prime Minister of Australia (between 1972 and 1975), considered closing the base. Victor Marchetti, a former CIA officer who had helped set up the facility, said that this consideration “caused apoplexy in the White House, [and] a kind of Chile [coup] was set in motion”, with the CIA and MI6 working together to get rid of the Prime Minister.”
From the Pine gap Wikipedia article, the whole article is a pretty good read.
“US diplomatic cables published last year by WikiLeaks disclose the names of leading figures in both main parties, including a future prime minister and foreign minister, as Washington’s informants during the Whitlam years.”
From the guardian article.
Is there anything definitive? not really,
Have either the US or the UK officially admitted anything? no of course not.
For me there’s enough to draw a conclusion. US and UK both have foreign policy records of ousting foreign governments for more closely aligned alternatives.