-- Flooding in Australia has affected more than 3 million people, making it one of the most costly disasters in the nation, the federal treasurer said Sunday.

The cost of the damage surpasses past tragedies like major bushfires two years ago and floods in the 1970s, Treasurer Wayne Swan said.

The cost of the recent flooding is much higher because of a spike in population in the state of Queensland, Swan said.

"While the state's whole population in 1974 was just 2 million, more than 3.1 million people have been affected by the latest floods," Swan said.

In his first economic note of 2011, Swan said "it's still too early to quantify the impact with any certainty at this stage." But he said there's "no question that the economic impact of these floods will be enormous."

Swan said the floods have devastated crops, tourism, retail and manufacturing and have disrupted major urban areas like Brisbane.

"One of the biggest casualties is likely to be our coal exports, with many mines shut down in big coal mining regions like the Bowen Basin, and supply chains severely hampered," Swan said.

"While this will be partly offset by higher prices, the loss of production will be hit much harder."

Swan said the government has already made about $227 million in disaster recovery payments to people who have been affected by the floods.

"Over the coming weeks, months and years, the Commonwealth Government will be investing billions of dollars to get Queensland back on its feet," Swan said.