Foreign Minister Bob Carr and former trade minister Craig Emerson lobbied their British counterparts earlier this year to urge Britain to remain a member of the European Union, amid a rising tide of Conservative demands for it to quit.
Conservative leader and British Prime Minister David Cameron has placated party rebels by promising to hold a referendum on EU membership by the end of 2017. He has not said which side he will support.
Documents released by a British review into the powers of the EU include a letter from Dr Emerson to British Business Secretary Vince Cable implicitly warning that Britain's withdrawal from the EU would damage Australian businesses that have their European offices in London.
"The UK attracts strong Australian investment partly due to our long term links but also because of the UK's position in the EU market," Dr Emerson wrote. "Australian businesses ... use the UK as a platform for trade and investment in the broader EU market."
Dr Emerson said the lure of "free movement of goods, persons, services and capital" to the wider EU market brought more investment to EU member states. He left unstated the implication that Britain would attract less Australian investment if it lost that free movement.
Senator Carr wrote to Foreign Secretary William Hague, praising Britain's "important and positive role" in shaping EU policies, adding: "I hope to see this continue long into the future.
"We appreciate the special role the UK has played in helping to shape the EU as an outwardly-focused institution, to the benefit of the international community", Senator Carr said. "The UK has championed free trade, the single market, and been a strong advocate on the need for the EU to remain competitive.
"Australia recognises the UK's strength and resilience and looks forward to seeing it continue as a leading economy and effective power. Strong, active membership of the EU contributes to this."
It is quite the opposite message to that sent to Britain 50 years ago by then prime minister Sir Robert Menzies and trade minister Sir John McEwen, who lobbied in vain to stop Britain joining the EU - fearing, correctly, that it would cost Australian farmers their privileged access to the lucrative British market.
Presumably Senator Carr and Dr Emerson concluded there was little chance of Britain again offering Australia special access for its beef, wheat and dairy products if it left the EU.
But Australia's lobbying, which has been matched by similar pleas from the US and Japan, appears to have fallen on deaf ears.
Conservative MPs voted unanimously this month for a private members' bill to support a referendum, and Mr Cameron tweeted his delight at its passage.
After nearly six years of an economy lurching from a crisis into the doldrums, the worst appears to be over for Europe. This month, the European Commission said it expected the 27-nation EU to emerge from recession in the fourth quarter of this year.
It forecast an economic expansion, accelerating to a 1.4 per cent growth rate next year. The eurozone, which is made up of the 17 countries that use the common currency, is projected to expand by 1.2 per cent.