Victorian public school teachers have told the Allan government their 28 per cent pay rise offer isn't good enough — and they're ready to strike again.

The Australian Education Union (AEU) confirmed on Friday that 57.7 per cent of its roughly 60,000 members voted against the draft deal, which had been agreed between the union's leadership and the state government last month.

It's a slap in the face for Education Minister Ben Carroll, who had touted the offer as making Victorian teachers "the best paid in the country together with the best conditions."

But the "no" camp — a well-organised internal faction — argued the 28 per cent over four years fell well short of their headline demand of 35 per cent over three years. They pointed to the mass walk-off in March, when 35,000 educators flooded Melbourne's streets, as proof the government could be pushed further.

AEU state branch president Justin Mullaly told members the government's May offer "has not gone far enough to address their concerns." He said the union would "strongly convey" that message to the government.

The sticking points aren't just about money. Teachers are also angry about conditions: unmanageable workloads, a lower pay offer for 35,000 education support workers, face-to-face teaching arrangements, flexible work, and the fact the deal was three years, not four.

Long-time union activist Lucy Honan, a key figure in the "No" camp, said the vote showed teachers wanted to keep confronting the government. "The mandate is now for pushing for huge transformations to public education," she told The Age. "The rank and file is going to be expecting strike action, and we will be organising it, one way or another."

The union's governing branch council — which had endorsed the deal and urged members to vote yes — will meet on Friday to decide next steps. But delegates opposed to the deal, gathering at the union's Abbotsford headquarters, said they were determined to secure commitments to further industrial action.

The political stakes are high. Victoria goes to the polls in November, and the union is a key Labor backer. If the dispute remains unresolved, the AEU won't be able to campaign for the Allan government.

A yes vote would have let Carroll sign a long-awaited agreement with the Commonwealth to bring state schools up to minimum funding — potentially neutralising education as an election issue. Now that's off the table.

Opposition education spokesperson Brad Rowswell was quick to pile on, saying the vote showed Carroll was "out of touch" with teachers. He suggested a Coalition government would prioritise a settlement if it wins in November.

Premier Jacinta Allan is now under pressure to step in. Rowswell demanded she give "an immediate assurance that she will do everything she possibly can to get back to the negotiating table and deal with this matter urgently."

For now, the ball is in the government's court. Teachers have spoken — and they're not backing down.