Ninja-clad petitioners "sneaked" into the office of Prime Minister Shinzo Abe on Wednesday to ask for help in promoting ninja culture as a tourism draw in the run-up to the 2019 Rugby World Cup and 2020 Tokyo Olympics.

"Even though you're all wearing such bright colors, you were still able to slip through the tight security" of the office, Abe told female lawmakers who were clad in pink and purple ninja outfits, drawing laughter.

The nine petitioners — four lawmakers and five members of the Japan Ninja Council, a body that honors the ancient mercenaries — handed requests to Abe written on two handscrolls.

"Many people abroad know ninja. We will utilize and disseminate the ninja culture," the prime minister said.

Practicing the art of ninjutsu (the way of stealth), ninja employed covert techniques while carrying out missions of espionage, sabotage and assassination, before gradually fading away during the Edo Period (1603-1868). They have become popular abroad through animation, manga, games and movies.

Eikei Suzuki, the governor of Mie Prefecture and head of the council, asked Abe to help arrange a shuriken (throwing star) demonstration by ninja during the opening or closing ceremony of the 2020 Tokyo Olympics and Paralympics.

The Mie city of Iga is home to one of the two most famous ninja clans, along with neighboring Koka in Shiga Prefecture.

The petitioners also proposed setting up venues to introduce ninja to foreign visitors during the Rugby World Cup and the Olympics.

The lawmakers were from the ruling Liberal Democratic Party's ninja-promoting group led by veteran House of Representatives member Keiji Furuya.