PRIME Minister Julia Gillard has assured South Australians she will work to ensure the River Murray remains healthy.

"I want to make sure that in the future SA families can take their kids to the mouth of the Murray and see water flowing," she said in Adelaide yesterday, hours before her trip was thrown into turmoil by the resignation of Foreign Affairs Minister Kevin Rudd.

Ms Gillard was asked about the Murray at a press conference after touring BAE Systems at Edinburgh with Premier Jay Weatherill. She later opened the Australian Industry (Ai) group's new building in Adelaide.

Mr Weatherill was lobbying the Prime Minister to ensure SA's interests were protected when the final Murray Darling Basin Plan was handed down later this year.

Ms Gillard said Mr Weatherill had already raised the question of the River Murray.

"He hasn't let a minute go," she said. "As someone who grew up in this state I understand the importance of the Murray for South Australians.

"I understand the frustration that has come over years and years, decades and decades, at the inability of our nation to get a national plan."

While the Prime Minister avoided the question of guaranteeing that SA's interests would be proctected when the final plan was handed down, she said: "I certainly want to assure SA of this, I want to see for the future the River Murray being a healthy river, the river communities being vibrant communities and upstream food production."

Ms Gillard said there were always going to be droughts and there were always going to be times of stress.

Ms Gillard said there should be a national plan so there was an understanding about conduct up and down the river rather than South Australians just bearing the brunt of conduct that happened upstream over which they had no control. Mr Weatherill said SA could not rule out any legal challenge to protect its rights on the river.

"We are not ruling out any of the rights we might have," he said.

"We are taking part in the consultation process in good faith. We believe we have rights in relation to the waters that come from the upstream states - a pretty fundamental proposition."

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