Suffolk County will hire a lawyer to pursue “any and all legal options” to block an influx of New York City migrants into the suburban community, local pols vowed at a contentious press conference Sunday.

Pro-migrant demonstrators repeatedly tried to shout down Republican county-legislature head Kevin McCaffrey as he announced plans for a special counsel to attempt to keep hundreds of Big Apple migrants from being bused to hotels and motels in the Long Island county.

“This is not an anti-immigration stance,” McCaffrey said over the constant taunts of the hecklers. “We recognize we are a country of immigrants. This is about the failed immigration policies of the federal government.

“We do not know who is going to be sent into this county, so we do not know what strain is going to be put on our partners in law enforcement.

“But we do know that [the county has] no way to provide for the food, shelter, medical or schooling costs,” he said, suggesting Dems President Biden and New York City Mayor Eric Adams were just kicking the can down the road.

Suffolk lawmakers said the reported $4.3 billion that New York City expects to ultimately spend on services and housing for the migrants through next spring is more than $1 billion above the entire county budget.

And what Suffolk would likely have to spend to deal with its own possible migrant influx would be just “a drop in the bucket” of what the eventual cost could be, McCaffrey said.

“We cannot allow the federal and state [governments] to pass on these costs to the residents of Suffolk County,” he said, adding that the board will move forward with “a procedural motion” to pursue “any and all legal options available to protect the unfounded location of any asylum seekers in Suffolk County.”

The announcement comes as New York City is being overwhelmed with thousands of migrants seeking asylum after crossing the US border with Mexico — including up to 900 per day last week and more than 4,200 in one week alone, Adams said on CBS News on Sunday.

He said the Big Apple has processed more than 70,000 migrants and has 42,000 “in our care.”

In a separate interview on MSNBC, Adams told host Jonathan Capehart that the White House and Democrats on Capitol Hill have to do more to help with the migrant burden.

“It’s time for us to sit down and speak with the president so that we can show firsthand how the impact of this crisis is undermining how we can your our function in our cities,” the mayor said. “This is just not sustainable for our city.”

Officials at City Hall did not immediately respond to a Post request for comment Sunday.

But Suffolk County officials said Sunday that Adams is just dumping the problem on them.

“If we are to maintain the greatness of being the greatest nation the world has ever known, we must continue to be a nation of rules and laws,” said US Rep. Nick Lalota (R-Long Island).

“Contrary to that, New York City officials have bragged for years that they were a ‘sanctuary city,’ that rules and laws did not apply to people who are in this country illegally if you are in the five boroughs,” he said, referring to the informal designation some cities such as the Big Apple have adopted to indicate they will generally try to protect illegal migrants from deportation.

“That is the policy choice that officials of New York City consciously made and bragged about for years.

“We here in Suffolk County are 2,000 miles from the southern border, but we are to become a border county because of the Biden administration’s failed border policy and the sanctuary-city policies of New York City, which has tended to become a magnet drawing people across that southern border.

“I say to the mayor of New York City, ‘Sir, put your money where your mouth is,’ ” Lalota said. ” ‘Those are your choices, sir. Now it’s time to put up the money and the resources to accept the consequences of those public choices.’ “