Financial stewards of the world's wealthiest economies gathered on Friday as demonstrators held a series of small-scale lightning protests ahead of a meeting due to focus on securing energy supplies.
Chest-high metal fences were erected and hundreds of police deployed on the streets of Melbourne in preparation for anti-globalisation protests when finance ministers and central bankers meet on Saturday and on Sunday as the Group of 20.
Several groups of shouting protesters entered and briefly occupied the lobbies of 14 commercial and government buildings in Melbourne, Victoria state Police Assistant Commissioner Gary Jamieson said.
One group squirted water pistols inside a defence building, damaging furnishings, he said. There were no arrests and the demonstrators left peacefully.
Protest organisers said they hoped to draw 10,000 people, and were urging those who came and police alike not to be confrontational. Police said demonstrations would be allowed, but illegal actions would not be tolerated.
Reform of the International Monetary Fund (IMF), rising interest rates, Chinese and Japanese currency levels and efforts to economically isolate nuclear-armed North Korea are also likely to come up at the two-day, closed-door meetings.
India, US and others said that the officials would also press ahead with talks on reforming the World Bank and IMF.
IMF Managing Director Rodrigo de Rato, who is attending the meetings, expressed satisfaction with the global economy.
"We would also like to sustain, and enable countries to benefit from, this period of unparalleled world growth - likely to approach 5 per cent next year - and low inflation," he wrote in Melbourne's The Age newspaper on Friday.