Opening the meeting of finance ministers and central bankers, Australian Treasurer Joe Hockey outlined an ambitious agenda of boosting world growth, fireproofing the global banking system and closing tax loopholes for giant multi-nationals.
"We have the opportunity to change the destiny of the global economy," said Hockey, who back in February launched a campaign to add 2 percentage points to world growth by 2018 as part of Australia's presidency of the G20.
That goal has seemed ever more distant as members from China to Japan, Germany and Russia have all stumbled in recent months. Just this week, the Organisation for Economic Cooperation and Development (OECD) slashed its growth forecasts for most major economies.
A call from U.S. Treasury Secretary Jack Lew for the euro zone and Japan to do more to boost demand and revive activity, signalling out Germany as having scope to do much more thanks to its burgeoning trade surplus, drew a cool response.
"We will not agree on short-sighted stimuli," a German G20 delegate said, arguing that in most countries debt was still too high to allow for increased spending.
Berlin has been under intense pressure to allow the euro zone to ease back on fiscal austerity and to stimulate its economy through more government spending or tax cuts.
GEOPOLITICS A THORN
The outlook for growth has not been helped by geopolitical tensions, from fighting in the Middle East to the strife between Russia and Ukraine.
Hockey said Australia, as the G20 host this year, had sought feedback from other G20 members on whether Russia should attend the meeting of leaders in Brisbane in November.
There had been calls from some quarters to block President Vladimir Putin from attending the summit given Russia's actions in Ukraine and the downing of airliner MH17.
The overwhelming consensus was that the door be left open to continue engagement with Russia, said Hockey.
Geopolitical tensions were also high on the agenda when financial policymakers of Japan, China and South Korea held their first trilateral meeting in more than two years in Cairns on Friday.
"We shared the view that we should strengthen our regional capabilities to manage financial and economic risks and respond to possible crisis," they said in a joint statement on Friday.
The meeting was the first since Prime Minister Shinzo Abe returned to power in 2012, after ties between Japan and its neighbours soured due to maritime territorial disputes and rows over the legacy of Japan's wartime aggression in Asia.
Also on the drawing board at the G20 are plans to stem the loss of revenue from multinationals shifting their profits to low-tax countries, potentially reclaiming billions of dollars.
Taxation arrangements of global companies such as Google Inc , Apple Inc and Amazon.com Inc have become a hot political topic following media and parliamentary investigations into how many companies reduce their bills.
The OECD has unveiled a series of measures that, if implemented by members, could stop companies from employing many commonly used practices to shift profits into low-tax centres.
Since countries began targeting cross-border loopholes five years ago, an additional 37 billion euros ($47.5 billion) in tax had been recovered, OECD Secretary-General Angel Gurria said, adding that firms were estimated to be holding $2 trillion in low- or no-tax countries.
"The whole world needs to go after tax cheats," Hockey said about the measures, which he hopes will be adopted by at least 44 countries.