Outgoing Labor senator Chris Evans is to tell his party colleagues to shut up and stop leaking to the media, saying they are undermining the government.
On Monday Prime Minister Julia Gillard demanded caucus colleagues stop leaking against her, after a fortnight when some had backgrounded journalists about discontent over dumped senator Trish Crossin, and her early election date announcement.
In an interview with ABC News 24, to be aired on Friday night, Senator Evans hits out at leakers in the party, saying: "Shut up; just shut up".
"No party can succeed if it's got people talking to people like you, offering negative views," Senator Evans says.
"I don't think it's in the interests of the Labor Party. Those colleagues who do that sort of thing undermine the government and they undermine their colleagues' chance of being re-elected."
Senator Evans, who last weekend announced his resignation, says all political parties are suffering from a growing culture of leaking to journalists.
"The Liberal Party does it," he says.
"The National Party does it.
"I think the culture of politicians leaking and backgrounding has really developed in a way that I think is unhealthy and not good for politics in this country."
The former Senate leader also backs Ms Gillard's decision to draft Olympian Nova Peris to the upper house, but expresses sympathy for the woman she will replace.
"(The ALP) has not been able to bring itself to preselect an indigenous person in a winnable seat in 100 or so years," he says.
"It was a disgrace. It was a blight on the party and the Prime Minister fixed that.
"I'm a great supporter of Trish's, and it's very unfortunate what's occurred in terms of her career, but it is something that needed to be addressed by the party.
"To be fair to the Prime Minister, the party machine have been unable to fix that wrong, and she's fixed it."