WASHINGTON (AFP) - The Federal Aviation Administration grounded all US-registered Boeing 787 Dreamliner aircraft on Wednesday to address a possible battery fire risk.

"As a result of an in-flight, Boeing 787 battery incident earlier today in Japan, the FAA will issue an emergency airworthiness directive (AD) to address a potential battery fire risk in the 787 and require operators to temporarily cease operations," the regulator said in a statement.

"Before further flight, operators of US-registered, Boeing 787 aircraft must demonstrate to the Federal Aviation Administration that the batteries are safe," it said.

The FAA said it would work with Boeing and carriers to develop a corrective action plan "to allow the US 787 fleet to resume operations as quickly and safely as possible." United Airlines, the world's biggest airline, is currently the only US airline operating the 787, with six airplanes in service.

The warning was prompted by a battery incident during an All Nippon Airways flight that resulted in an emergency landing in Japan on Wednesday, following a Jan 7 battery incident on an ANA 787 that occurred on the ground in Boston.

"The AD is prompted by this second incident involving a lithium ion battery. The battery failures resulted in release of flammable electrolytes, heat damage, and smoke on two Model 787 airplanes," the FAA said.

"The root cause of these failures is currently under investigation. These conditions, if not corrected, could result in damage to critical systems and structures, and the potential for fire in the electrical compartment."

The FAA said that it also is alerting the international aviation community to the action so other civil aviation authorities "can take parallel action to cover the fleets operating in their own countries."