The two largest domestic airlines have upped their competition by both filing for government approval to offer one-way fares of 7,700 yen on their principal domestic flights for five days starting on Oct. 1.

If the applications from Japan Airlines Corp. and All Nippon Airways Co., filed Tuesday, are approved by the Ministry of Land, Infrastructure and Transport, passengers will have to book flights between Aug. 1 and 10 to get the deal. There only will be a limited number seats at the special price on each flight, according to JAL and ANA officials.

This round of price undercutting was kicked off when JAL announced on July 14 that it would apply to offer a one-way fare of 8,000 yen on domestic flights Oct. 1-5 to mark the integration of its domestic and international flight-service units in October.

ANA countered JAL's move Tuesday by applying to the ministry for a 7,700 yen, prompting JAL to follow suit later in the day.