The Greens plan to capitalise on Labor's suspension of a pro-Palestine senator to target seats, pressuring government MPs to take a stronger stance on the issue.
Labor parliamentarians on Tuesday officially endorsed Prime Minister Anthony Albanese's suspension of Senator Fatima Payman for supporting a Greens Senate motion supporting Palestinian statehood.
The Greens are mulling whether to move another pro-Palestine motion in the Senate to force Senator Payman's hand a second time.
While there is no mandated sanction for defying the party's position, Labor members have traditionally been suspended or expelled.
Mr Albanese told Labor's caucus meeting on Tuesday he had received criticism for showing restraint but "some compassion is a strength not a weakness".
He pointed out Senator Payman was elected because she ran as a Labor candidate.
The senator has placed herself "by her own actions and statements outside the privilege that comes from participating in the federal parliamentary Labor Party caucus".
"This is the most united caucus I've have been a part of," Mr Albanese told the party room.
She could return if she pledged to respect party processes, he said in question time, after she vowed to cross the floor again if the same motion was put.
There was no debate in the morning caucus and the motion was agreed to unanimously, a party spokesman said.
The Western Australian senator has been stripped of voting duties but said she would vote on matters of conscience.
She was also absent from question time on Tuesday.
Greens Leader Adam Bandt said he would continue to pressure Labor to take a stronger stance against Israel and support Palestine and those in Gaza.
He denied he had conversations with Senator Payman about jumping ship to the Greens, saying it was not about politics but getting Labor to shift its position.
"Labor should stop putting pressure on Senator Payman," he said.
A Greens doorknocking campaign will target Labor's Peter Khalil, Ged Kearney, Justine Elliott, Patrick Gorman and Graham Perrett.
"If Senator Payman can cross the floor on a matter of principle you should as well," Mr Bandt said of the Greens' message.
But senior ministers have defended Mr Albanese's handling of the ordeal, saying while Labor welcomed a diversity of views inside the partyroom, MPs were expected to be team players with a premium on unity.
"We've made clear that we would welcome her back into the caucus," cabinet minister Murray Watt said.
The government had put forward its own amendment to the Greens motion which would have recognised a Palestinian state as part of a two-state solution and a peace process, he said.
"That's a very reasonable position for the caucus to take, it reflects a lot of the views in the community, and we welcome Fatima's support on that issue and everything else," Senator Watt said.
Senator Payman has since described being isolated and said she was being pressured to quit after her punishment was handed down.
Health Minister Mark Butler rejected the senator was being intimidated, saying Mr Albanese had followed established party policy.
Voting as a bloc was not a new position, he said.
Deputy Liberal Leader Sussan Ley urged the prime minister to investigate any allegations of bullying against Senator Payman.
"It shouldn't have been beyond the prime minister to show the leadership required to deal with this issue without putting a 29-year-old woman in a position where she feels intimidated by her colleagues," she said.
Colleagues were "desperately trying to reach out and provide support where they can", Finance Minister Katy Gallagher said.