Americans in Lebanon should leave now while flights are still available, White House national security spokesman John Kirby said on Tuesday, as violence flares between Israel and Hezbollah along the Israel-Lebanon border

"We want to make sure that there are still commercial options available for Americans to leave, and they should be leaving now while those options are available," Kirby told ABC News' "Good Morning America" program, adding that U.S. officials have been in constant contact with Israeli counterparts.