In response to a spate of incidents where mobile batteries emitted smoke or caught fire on aircraft, their use during flights is likely to be effectively prohibited in Japan, sources said.

As the U.N.’s International Civil Aviation Organization discusses rule changes on power banks, it is considering recommending a ban on in-cabin use.

The transport ministry is expected to follow its recommendations and domestic airlines would call on passengers to refrain from using mobile batteries, meaning they would have to remain off while aboard a plane, the sources said.

The ministry is also considering limiting the number of portable batteries passengers are allowed to bring on board, regardless of their power capacity.

The ICAO is expected to finalize new regulations at a council meeting in March.

Following that decision, the ministry plans to revise a public notice under the Civil Aeronautics Law, which governs rules on what may be brought onto aircraft.

In Japan, mobile batteries currently fall under spare battery regulations, such as ones for cameras.

Current rules state that spare batteries exceeding 160 watt-hours are prohibited in carry-on baggage, while those exceeding 100 watt-hours are limited to two units. Batteries with a capacity of 100 watt-hours or less are not subject to any numerical limit.

All such batteries are prohibited in checked baggage.

The ICAO is deliberating on a proposal to limit the combined total of both spare and mobile batteries to two units, the sources said.

Under the proposal, the number of mobile batteries allowed would be cut off at two regardless of their power capacity. Those exceeding 160 watt-hours would still be prohibited.

Limits would not be imposed on spare batteries with capacities of 100 watt-hours or less.

In January last year, an Air Busan passenger aircraft was partially destroyed after a power bank caught fire on board at Gimhae International Airport in South Korea. All 176 passengers and crew members were evacuated, but 27 were injured.

In Japan, a mobile battery caused a fire last April on a Hawaiian Airlines flight from Honolulu to Haneda. Another began emitting smoke on an All Nippon Airways flight from Naha to Haneda in October.

Since last July, major domestic airlines have been asking passengers to keep portable batteries at hand or immediately visible instead of stowing them in overhead compartments.