New Jersey will likely not see any legal marijuana sales until January at the earliest, the Senate president said late Thursday.

The remarks come as Gov. Phil Murphy, Senate President Stephen Sweeney and Assembly Speaker Craig Coughlin, all Democrats, are making progress in negotiations over a sweeping package of legislation to legalize marijuana for recreational use, expand the state's medical marijuana program and overhaul the rules for expunging drug-related and other violations.

The trio last week resolved a longstanding disagreement over how to tax legal weed sales and settled some aspects of how a new regulatory system would work. But a final compromise remains elusive.

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Even when the bills are finalized, Democratic leaders face an uphill battle convincing enough lawmakers to vote for them. Then the state needs time to set up rules and regulations before sales can begin.

“I think the best-case scenario is you’re going to have marijuana actually available legally, ehh, January,” Sweeney told reporters Thursday. “That’s the fastest you’re going to get it.”

Sweeney confirmed details of his negotiations with the governor and Coughlin that were leaked to the press last Friday. Rather than levying a sales tax on marijuana sales, as had been discussed previously, the Democrats now agree the state should impose a flat tax rate of $42 per ounce of marijuana.

Such a tax system protects the state from a sudden loss of revenue should the price of marijuana drop dramatically, as has occurred in other states that have legalized recreational marijuana.

The men also agreed to allow the governor to appoint three members to the five-member board of a new Cannabis Regulatory Commission without requiring confirmation by the Senate, a shift from an earlier proposal that would have given the Senate oversight.

In earlier negotiations, Murphy had opposed the idea of creating a stand-alone commission at all.

But Sweeney said other aspects of the commission still need to be worked out, such as when and how it will be able to adjust the tax rate to help reduce illegal sales. Sweeney said he worries that if the tax rate is set too high, the black market will continue to flourish, eating into legal sales and state revenue.

“If you’re not getting the sales and you’re not generating the tax dollars, what’s the sense of having a high tax rate?” he said Thursday.

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While negotiations continue, New Jersey residents continue to warm up to the idea of marijuana legalization.

Sixty-two percent of residents favor the policy, according to a Monmouth University Poll released this week. That’s the highest approval rating ever recorded in the state.

Five years ago, another Monmouth University Poll showed public sentiment split, with 48 percent in favor and 47 percent against.

Email: pugliese@northjersey.com