Mr Little said the Government had approached Labour because it did not have the numbers to pass the legislation.
United Future plans to vote for the bill at the second reading but wants the Government to agree to firm up compensation for workers whose shifts are cancelled.
The Maori Party said it was still in discussions about its position. Co-leader Marama Fox said she was concerned about zero hours contracts, in particular employees' ability to advocate for themselves.
"These are people who probably may not have the capacity ... to go to court or to take it up with their employer."
Workplace Relations Minister Michael Woodhouse said minor parties had been misled on the legislation. He planned to meet with leaders to get them back onside.
But he was confident that the Government had the numbers to pass the legislation this month -- before provisions on paid parental leave must come into force.
Mr Woodhouse said the bill was "in very good shape" but he was open to making further changes.
"I've had an approach from a couple of people about how it could be improved in a small way and I'm considering them."
The legislation also extends paid parental leave to a broader range of caregivers from April 1.