A former JFK cargo worker charged with plotting to blow up the airport’s fuel tanks and gas lines told cohorts that they should aim for Christmas Eve 2008 because security workers tended to get lazy around the holidays, an informant testified yesterday.

FBI mole Steven Francis also said suspect Russel Defreitas — a Guyanese national on trial in Brooklyn federal court — videotaped the tanks for al Qaeda bigs in the hopes of getting their financial backing.

“[A bombing] will take out the whole area, the whole of Kennedy would go up in smoke,” Defreitas is overheard saying on an FBI tape.

“A few people would escape, but to where? Jamaica Bay?”