The Port Authority’s top boss at JFK Airport abruptly quit his $179,600-a-year position without explanation Monday, sources told The Post.

Gennaro “Jerry” Spampanato, 75, JFK’s general manager, notified PA officials of his intention to retire from the nation’s sixth biggest airport effective immediately,  a PA official said.

Another PA official, however, disputed that account, insisting that Spampanato’s departure was not voluntary and that he’d been effectively fired.  “People don’t quit positions like that without a reason and giving notice,” the source said.

Reached at his home in East Meadow, LI Monday last night, Spampanato acknowledged having left, but refused to discuss the circumstances.

“I have no comment,” he said.

Spampanato is being temporarily replaced by Huntley Lawrence, the PA’s deputy director of aviation.