When it comes to the New York pot rush, Manhattan District Attorney Cy Vance is anything but a buzzkill.

The borough’s top lawman spoke to marijuana enthusiasts and entrepreneurs on Tuesday night about the “future” of cannabis in NYC — and told them flat-out that he was rooting for their success.

“I want you all to be successful and legal,” Vance said, noting how the Big Apple was the largest black market for pot in the country.

“New York needs to take a lead responsibly — with speed,” he added.

Vance was invited to speak at CannaGather, a monthly meetup for industry hotshots, as a result of his office’s lenient stance on marijuana.

He enacted a new policy last month — ending the prosecution of low-level marijuana cases — as part of a broader city trend toward decriminalization.

“Our office, if the NYPD makes an arrest, will not prosecute a possession of marijuana for low-level possession or smoking a joint, unless you’re observed selling marijuana, and the buyer runs away from the police and we can’t find the buyer,” Vance explained Tuesday. “I think we can perhaps, we can all agree — because you’re in the business of marijuana — you should be licensed when you sell. Selling is simply different than possession and therefore that’s something you can and should be prosecuted for.”

Vance urged those in attendance — many of whom were venture capitalists, investors and product developers — to set their sights on the Big Apple now that it appears to be on the brink of making weed legal.

“To all of you out there who I know are entrepreneurs, or thinking about whether this is a business you have a future in: I think marijuana legalization is coming to New York,” Vance said.

“Before we made our change in policy, we spent six months traveling the United States, going to those states where marijuana had been legalized, talking to prosecutors, chiefs of police, the agency heads … When we looked at how it was working — and our policies — my conclusions as DA, [is] that we didn’t, in New York state, have to be afraid of legalization.”

Vance said that what officials ultimately need to do now is “manage” the progress of marijuana and avoid the mistakes other states have made after legalizing.

“[We need to] start doing the things states didn’t do early on, so when the legislature moves to legalize it, there’s a rational process forward that voids those pitfalls other states have had,” Vance explained. “Some states have, from a business perspective, issued too many licenses. When you issue licenses in a state, you don’t want to drive prices so low that you encourage black market sales. You have to carefully manage as business and a licensing perspective how you’re going to manage the market.”