At the coalface it's the capacity to deliver

VICTORIAN Labor leader Daniel Andrews has unleashed a withering attack on the Greens and taken a swipe at the Gillard government.

VICTORIAN Labor leader Daniel Andrews has unleashed a withering attack on the Greens and taken a swipe at the Gillard government as the tensions between the ALP and the minor party intensify.

Mr Andrews dismissed the Greens yesterday as being impotent while they pursued an "evangelical idealism".

Mr Andrews said the Greens were more comfortable being on the political sidelines and a vote for the party in the July 21 state by-election for Melbourne was a waste of time. He also claimed that federal issues were making state Labor's chances of holding a seat it had held for more than a century that much harder.

"There (are) a whole range of issues in place in the Melbourne by-election," Mr Andrews said.

"It's not just state issues, there are some other federal issues as well. But I do not seek to focus on this to soften people up for what will be a very challenging race."

He urged voters to "call the Greens out" because even if the party's candidate, Cathy Oke, secured the 6.2 per cent swing needed to win, she would not have influence over parliament. "Their main game is holding themselves hostage to their own ideals, to an evangelical idealism that achieves nothing," he said.

Greens state MP Greg Barber said Labor was so concerned about losing Melbourne, after the resignation of sitting MP and former minister Bronwyn Pike, that they were resorting to slurs.

"They're desperate," he said. "He (Mr Andrews) risks being the Tony Abbott of Victoria, relentlessly negative and (with) nothing to say on his own party's account."

The brawl between the two parties comes after The Weekend Australian revealed that NSW Labor secretary Sam Dastyari was backing putting the Greens last in federal election preference deals.

Victorian Labor has for years been waging a battle with the Greens in inner-city electorates, although Mr Andrews yesterday stopped short of preferencing the party out of existence in those seats.

Such is the concern about the Greens' momentum in the seat that Labor has done a preference deal with the conservative Family First party.

The Liberal Party is not contesting the seat but ALP candidate Jennifer Kanis is fighting a vigorous campaign against the Greens, who have announced nine policies so far, ranging from planning to further education and public transport.

Mr Andrews defended Labor's decision to preference Family First ahead of the Greens.

"I'm about winning government, I'm about getting rid of (Victorian Premier) Ted Baillieu, and we'll make preference decisions that maximise our chances of winning," he said.

There is no Liberal among the 16 candidates.