People in Japan are dressing down.

The nation began its annual Cool Biz energy-saving casual wear campaign.

The Japanese environment ministry launched the drive to reduce power consumption by limiting use of air conditioning.

Now in its 10th year, the campaign has wide support.

An increasing number of workers at firms and government agencies can be seen dressed lightly.

During the Super Cool Biz period from June to September, some will even be allowed to wear aloha shirts.

Employees in a Tokyo business district were seen without neckties this morning.

Some wore Kariyushi shirts, an Okinawa shirt similar to aloha shirts.

Cool Biz continues until the end of October.