Tokyo - Boeing's 787 Dreamliner is poised to resume flights in Japan, ending a more than three-month hiatus that grounded 24 planes owned by ANA Holdings and Japan Airlines.

ANA said Friday it will conduct the jet's first test flight on April 28, after Japan approved restart of the 787 flights with upgraded batteries. The government's permission is for all flights, including test and commercial services, said Shigeru Takano, a director at the ministry's Civil Aviation Bureau.

"We will ask Japanese airlines to ensure the safety of passengers and provide them with information," Akihiro Ohta, Japan's transport minister, told reporters in Tokyo.

The move will kick start resumption of flights with 787s, grounded worldwide on Jan. 16 after lithium-ion batteries on two separate planes overheated and melted, causing flights to be canceled and cutting revenue at the operators. The grounding is the longest on a large commercial aircraft by U.S. regulators since jets were introduced in the 1950s.

Shinichiro Ito, chief executive officer of ANA, and Ray Conner, Boeing Commercial Airplanes President, will be on board the April 28 test flight, the airline said in a statement today.

Boeing dispatched about 300 personnel on 10 teams to airlines to install the fix over five days while preparing the handover of new 787s.

Tokyo-based ANA started repairs earlier this week at four airports around Japan, according to Ryosei Nomura, a spokesman. JAL also started fixing the batteries, according to a person familiar with plan, who declined to be identified as the information isn't public.

ANA will conduct about 230 test flights for pilots with the upgraded 787s, Hiroyuki Ito, a senior executive vice president, told reporters today. The carrier will also check battery systems after flights. Final checks are going on at five Dreamliners after battery fixes, Ito said.

The airlines received service bulletins on repairs from Boeing after it won approval from the FAA for the 787's redesigned battery system. The cost for replacing the battery will be about $465,000 a plane in the U.S., FAA said yesterday. The battery fix adds about 150 pounds of weight to a 787.

Neither the FAA nor the NTSB has determined what caused the battery faults that sparked a Jan. 7 fire on a JAL 787 in Boston and forced an emergency landing by an ANA jet in Japan nine days later.

Japan will ask airlines to put in place a system to monitor the batteries in flights and transmit data to the ground, Ohta told reporters today.

Boeing's reworked battery includes more protection around the cells to contain overheating, a steel case to prevent any fire from spreading and a tube that vents fumes outside the fuselage.