Gov. Phil Murphy's administration put New Jersey's state agencies on notice Friday that they should prepare for another state government shutdown if a state budget isn't signed by the June 30 deadline.

The letter to Murphy's cabinet members, obtained by NJ Advance Media, asked them to update contingency plans for their departments.

It was sent shortly after top staffers in the state Senate and Assembly met with Murphy's senior staff Friday morning amid ongoing negotiations about Murphy's first state budget proposal -- which so far have been fraught.

The meeting was tense and unproductive, according to six sources with knowledge of the event who would speak only on the condition of anonymity. One source described it as "ugly."

Shortly thereafter, Murphy's chief counsel, Matthew Platkin, ordered state agencies to submit their shutdown contingency plans to the governor by noon on June 11.

It would be the second straight year that New Jersey's government shut down over July 4th weekend because of a dispute at the budget deadline.

Friday's meeting came a day after state Senate President Stephen Sweeney -- New Jersey's second-most powerful elected official -- introduced a plan to revamp the state's school funding and said he was willing to risk another shutdown to get it done.

Sweeney, D-Gloucester, is also angry about a pro-Murphy ad that an independent group with ties to the governor is preparing to air.

A script for the TV spot has Murphy on camera touting the accomplishments of the first five months of his administration.

But Sweeney views it as putting pressure on lawmakers to agree with the governor's $37.4 billion budget plan -- which includes $1.5 billion in tax hikes -- when the negotiations should happen in private.

Murphy downplayed the ad during an unrelated event in Woodbridge on Friday morning.

"Frankly, the script looks so divisive, I wouldn't be surprised if the Russians were involved," Murphy quipped.

But Sweeney isn't laughing.

He says Murphy, along with state Assembly Speaker Craig Coughlin, D-Middlesex, should be discussing the budget with each other -- not over the airwaves.

"If you read the ad, it's basically saying we need to do all the things he's asking for in the budget and we need revenues," Sweeney told NJ Advance Media in a phone interview Friday. "Pretty simple. That's the stuff we should be negotiating."

One source said the situation between Murphy and Sweeney -- who have had a rocky relationship thus far -- is currently "as bad as it gets."

Another source said it appeared Murphy's team was manufacturing political drama with Friday's meeting.

The sit-down ended shortly after Platkin, Murphy's counsel, and Kevin Drennan, the executive director of the state Senate and a top Sweeney aide, exchanged words about Sweeney's school funding plan, according to two sources.

Platkin abruptly left the room out of anger, the sources said. Hours later, he released the memo warning of a shutdown.

Drennan confirmed he was in the meeting but said "the characterizations that have been reported are inaccurate and overblown.

"I don't believe it is appropriate to be talking publicly about what transpired in private discussions," Drennan added in a statement. "Our goal is to get things done, not to create distractions."

The drama comes a year after a budget dispute between then-Gov. Chris Christie, a Republican, and leaders of the Democrat-controlled state Legislature shut down the state government for three days.

State parks, beaches and agencies were shuttered over July 4th weekend. And NJ Advance Media captured widely circulated photographs of Christie lounging on the sand outside the governor's summer house at one of the closed state beaches.

Now, Murphy, a Democrat, is in charge. But legislative leaders from his own party disagree with his first state budget proposal.

They have pushed back against Murphy's plans for a new tax on millionaires and reverting the state sales tax from 6.625 percent back to 7 percent to increase funding for education, transportation and more.

Legislative leaders are considering crafting their own budget with no millionaires tax or sales tax increase to send to Murphy, according to multiple sources. It would include Sweeney's school funding plan, legislative add-ons that Murphy nixed and additional money for homestead rebates.

If Murphy and the Legislature don't agree to a budget by June 30 -- the end of the fiscal year -- that will trigger another shutdown.

And the way it stands now, state parks and beaches would be closed again. A bill being considered in the Legislature to keep them open amid another shutdown has not passed yet and it's unclear if it will by the end of the month.

The bill, introduced last year, would require those sites to remain open for seven days in the event of a shutdown.

The circulation of the memo was first reported by Politico New Jersey.

NJ Advance Media staff writer Samantha Marcus and S.P. Sullivan contributed to this report.

Matt Arco may be reached at marco@njadvancemedia.com. Follow him on Twitter @MatthewArco or Facebook.

Brent Johnson may be reached at bjohnson@njadvancemedia.com. Follow him on Twitter @johnsb01.