She flew into Bundaberg, where the flooding has already peaked, before heading to Rockhampton, where waters are expected to rise.

The floods have affected about 200,000 people over an area bigger than France and Germany combined, according to Queensland Premier Anna Bligh.

Some 4,000 people have been displaced.

Ms Gillard's first stop was in Bundaberg, which has seen its worst flooding for four decades and has been split in two by the swollen Burnett River. Waters there are now receding.

She spoke to evacuees and volunteers, and was briefed on the rescue and recovery effort.

The prime minister is also hoping to visit Emerald, a town of about 11,000 residents in central Queensland where waters have reached about 16m (52ft) and more than 1,200 people have been evacuated.

Helicopters including Army Black Hawks have been ferrying residents to safer locations.

Two smaller towns, Theodore and Condamine, have been completely evacuated. In Condamine some residents had been refusing to leave their houses.

Further north, Rockhampton is bracing for rising water that officials say could cut the city off by the weekend.

Officials have warned of severe damage to homes, crops and livestock. Sewerage systems have also been affected, raising public health concerns.