Foreigners arriving at Narita airport waited an average of 13 minutes and a maximum of 44 minutes to get through immigration on a busy weekend earlier this month, the government said Tuesday.

Given the situation, the Justice Ministry said it will operate immigration booths at the country's main international gateway with greater flexibility, including freeing up some of the re-entry booths for Japanese, to reduce the waiting time for foreign visitors.

The Justice Ministry's Immigration Bureau did not study the waiting time for returning Japanese.

The survey was conducted in response to an opposition lawmaker's claim in a Diet session in November that foreigners frequently wait in line to enter Japan at Narita for more than an hour.

In response, Prime Minister Junichiro Koizumi urged immigration and airport authorities to improve the system at Narita in line with the government's ongoing campaign to double the number of foreign visitors to Japan by 2010.

According to a similar study last January, foreigners waited an average of 12 minutes and a maximum of 33 minutes to go through immigration at Narita, while Japanese people took an average of only three minutes.

To ease the inconvenience, the Immigration Bureau said it will allocate inspection booths for foreigners and Japanese with more flexibility.

Currently, the airport's No. 1 and No. 2 terminals combined can have up to 60 booths open for immigration and re-entry procedures, and usually allocate the same number of booths to Japanese and foreigners, bureau officials said.

Inspectors will also frequently move between the two entry sections at Terminal No. 2 when one becomes more congested than the other.

The bureau will discuss with airport authorities arranging arrival-gate schedules to prevent one section from receiving too many visitors, the officials said. The bureau will set up special booths for elderly, disabled and pregnant visitors.