TRENTON — Gov. Phil Murphy says the school-funding overhaul being advanced by the Legislature after months of negotiations with his office is “a very good path” forward – but isn’t sustainable unless lawmakers find a different plan for tax hikes.

A day after pressing the case for his budget at the Trenton Transit Center, Murphy did the same Wednesday at the state Department of Education headquarters. This time, he substituted school funding for transit subsidy as part of the hard sell.

“Make no mistake: We have made tremendous progress over the past three months,” Murphy said. “However, until we have an agreement on sound and sustainable revenues, we cannot have an agreement on school funding.”

Murphy called the budget plan “the ultimate half a loaf” when it comes to school funding because the changes to the funding formula aren’t matched by recurring revenue.

Democratic lawmakers intend to approve a two-year surcharge on business taxes that they think will generate $805 million and offer tax amnesty until December for anyone with unpaid liabilities incurred since 2012. Legislators think the amnesty will yield $150 million.

They’re not planning to OK increases Murphy seeks in the sales tax and on income over $1 million.

Murphy says that makes the school-funding revisions unsustainable and that he “simply will not be a part of that.”

“As governor, I cannot commit the state to a new school funding formula without knowing that we will be able to keep the promise beyond the 2019-2020 school year,” he said.

“I cannot and I will not tell these families that we’ve solved their problem when we know we’re going to be just right back here again two years from now if not sooner trying to think up new ways to dig up extra cash because we didn’t do our homework the first time,” Murphy said.

Some of those families Murphy referenced, from towns that are receiving millions of dollars less each year in school aid that the funding formula would provide if it was followed, were in the Department of Education building but denied entry to the governor’s news conference.

“How do you deny access to parents, administrators and students who have taken days off of work to come here and listen to him talk about how he plans to fund education and his priorities in education?” said Jennifer Cavallaro-Fromm, a member of the Kingsway Regional school board.

There were also representatives locked in the hallway from Manville, Robbinsville and Chesterfield, which are all members of a group called the Fair Funding Action Committee that supports the school funding changes lawmakers are advancing, in bill S2/A2.

“I just really wish the governor would support it so we all know where we’re going next year, and we don’t have to keep coming back to those budget hearings and keep showing up to press conferences that they won’t even allow us into because – I don’t know why,” said Chesterfield Township Committeewoman Andrea Katz.

Murphy said he does support it – if permanent tax increases are approved.

“It’s a very good path that’s been laid forward, assuming it’s funded,” Murphy said. “That overwhelms, that dwarfs any of the elements of this.”

Cavallaro-Fromm said she disagrees with that philosophy and backs the Legislature’s budget. She said “there definitely does need to be additional revenue sources implemented to have it sustained fully” but that redistributing $670 million in existing aid over seven years would be a “huge down payment.”

“And then in the two years, you have the time to look at the federal policies and the state policies to see what you can do in terms of tax increases that doesn’t kill the middle class, which is essentially everybody sitting in this room,” Cavallaro-Fromm.

There are 10 days left to adopt a budget in time to avoid a potential state government shutdown.

Lawmakers say Murphy isn’t talking with them, but he says he’s willing.

“I’m available every second of every hour in every day,” Murphy said. “And the only price of admission for that conversation, there’s only one price – that folks come to the table with sustainable, long-term revenue sources. And that’s the price of admission.”