They protested against a range of new budget measures including the introduction of fees to visit a GP, the deregulation of tertiary education, and a broken promise to not cut the ABC's budget.

The crowd swelled from hundreds before the mooted kick-off time at 1pm, and estimates of total numbers gathered for the march in Melbourne varied from between 12,000 up to 20,000.

Luke Hilakari, Victorian Trades Hall campaigns officer, said that this rally was particularly special because, for the first time, over 80 different community groups, including churches and environment organisations, were uniting for a single cause.

"We want Tony Abbott to scrap this budget," Mr Hilakari told protesters. "We reckon rallies like this give courage to senators to stand up for all Australians."

Strewn amongst the banners flagging the presence of the Australian Nursing and Midwifery Federation and the Australian Services Union were a range of hand-crafted signs promoting more personal agendas, including "turtles need a safe climate," "unicorns say no!" (held aloft by a small girl in a unicorn onesie) and a poster featuring the perennially disapproving internet-star "Grumpy Cat."