TOKYO (AP) -- Japan's All Nippon Airways, the launch customer for Boeing's 787 "Dreamliner," will resume commercial flights of the aircraft on Sunday, just over four months after the jets were grounded due to smoldering batteries.

ANA said in a statement that it will run five commercial 787 flights in May, before regular, scheduled services begin on June 1. The first will be a commercial flight late Sunday from Chitose, on the northern island of Hokkaido, to Tokyo's Haneda Airport.

Smoldering batteries on two 787s, one of them owned by ANA, prompted authorities to ground the planes in January. The failure of Boeing's newest, flashiest and most important plane embarrassed the company and its customers.

ANA said it has modified all 17 of its 787 aircraft and conducted 170 proving flights.