A Borscht Belt brouhaha is brewing.

The state is entertaining developer Louis Cappelli’s long-delayed plan to build a massive $600 million harness track and casino resort on the site of the former Concord Hotel in Sullivan County — within four miles of Monticello Casino and Raceway.

The very idea has Empire Resorts, which runs Monticello and which considered a joint venture with Cappelli before bailing out, crying foul.

And experts agree that Cappelli’s Concord project could put Monticello gaming out of business.

“Sparsely populated Sullivan County cannot support two racinos less than a few miles apart,” said Empire Resorts Chairman Emanuel Pearlman.

But Cappelli — ironically, one of Empire Resorts’ largest shareholders — insists the two gaming institutions can co-exist.

“I want to be able to draw millions of people to the Catskills again,” he said. “I believe the Catskills can support two casinos.”