Yesterday Senator Joyce described Mr Abbott's decision last week to dump him from the finance portfolio as ''you lose one girlfriend, you find another one''. He then waded into what he said was a ''red hot'' water debate.

The opposition's water, infrastructure and regional development spokesman told Weekend Today on the Nine Network he intended to engage all of the key interest groups on his doorstep over the Murray-Darling issue.

''I want to make sure we get right around the basin from Adelaide right up to Toowoomba and start talking to these key interest groups … and if we can come to an agreement, then we don't need a referendum,'' Senator Joyce said.

The manager of opposition business, Christopher Pyne, told Meet the Press on Channel Ten yesterday that the Coalition's policy on the Murray-Darling Basin was clear.

''We believe the states have failed to govern the Murray-Darling Basin in the interests of the almost 2 million people that live in the Murray-Darling Basin … We want them to refer their powers to us in the middle of next year,'' he said.

Mr Pyne said he had spoken to Senator Joyce and he agreed ''that the Murray-Darling Basin must be managed for everybody who's in it and that a referendum is a last resort''.

However, the Minister for Climate Change, Penny Wong, said that Senator Joyce's comments showed he was ''just as much risk to the Murray-Darling Basin as he was to the nation's finances''.

She said Senator Joyce seemed to think ''that because there's water rushing past his front door, the rest of the nation's got nothing to worry about''.

''Any referendum the National Party allows will take us back to the bad old days of parochial interests controlling the Murray-Darling Basin - and will make South Australians the biggest losers,'' she said.