All Nippon Airways says flight cancellations associated with the grounding of its Boeing 787 fleet will reduce its revenue for the month of January by Y1.4 billion ($15.4 million).

Since the grounding of the 787 on 17 January, ANA says it has cancelled 459 domestic and international flights.

"It remains unclear as to when the aircraft will resume normal service," it adds.

ANA made the disclosure in its results announcement for the nine months ended 31 December 2012.

The US Federal Aviation Administration issued a directive ordering the grounding of all US-registered 787s on 16 January, after an ANA 787 had to make an emergency landing because of a battery problem. Regulators worldwide have since issued similar directives to ground the aircraft type.

ANA, the launch customer of the 787, operates 17 examples of the type.

Source: Air Transport Intelligence news