BOSTON (CBS) — Phase 3 of the Massachusetts reopening plan begins Monday, Gov. Charlie Baker announced. But even though coronavirus numbers here are trending in the right direction, it could be a long time before the state enters Phase 4 and allows bars, nightclubs, amusement parks and other large capacity venues to reopen.

“Phase 4 is therapeutics or a vaccine,” Baker reiterated Thursday. When asked by a reporter if there was any chance that some of those businesses could reopen early, the governor simply replied “no.”

Texas and Florida have ordered reopened bars to shut down again after seeing a surge of coronavirus cases. Infectious disease expert Dr. Anthony Fauci told a Senate panel this week that congregating inside at bars is “bad news.”

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“The primary driver of much of the significant increase in positive tests in a number of states has been the reopening of bars and nightclubs, and obviously bars and nightclubs are sitting in Phase 4 under our guidance, and there is a reason for that,” Baker said. “As difficult as it is for the people who operate and work in those institutions, we could not figure out a way to do that safely. And I think some of the indicators we’ve gotten from other states that moved forward with those is that they couldn’t figure that part out either.”

A coronavirus treatment needs to “enable resumption of a new normal” in order to trigger Phase 4, according to the state. Dr. Fauci said there’s “no guarantee” that there will be a safe and effective vaccine soon, but he’s hopeful that vaccine doses will be available by the beginning of 2021.