STOCKHOLM, Sweden (AFP) - The Swedish town of Lulea, home to some 80,000 inhabitants, has launched a campaign encouraging residents, who are reputed to be introverts, to start talking to each other.

In a video posted on social networks, residents of Lulea, located 150 kilometres (93 miles) south of the Arctic Circle, with stern faces suddenly light up when they meet a passer-by who greets them.

The video is accompanied by a message: "Saying hi to your neighbours is a small thing, but research shows that it can contribute to social bonds and has a positive impact on health, safety, and well-being."

Asa Koski, a social strategist with the municipality, who is behind the campaign, told AFP that the message has been displayed on buses and buildings in the city since October 31, and the campaign will run for four weeks.

"Swedish people can be a bit inward... We need to connect with each other, and this is a way to create relationships.

"Here it's the opposite of Spain where you are outside a lot, you talk to people, you sit on benches, you have a collective life outside," she said.

Local schools are also organising screenings of the video, and Koski explained that surveys have showed that people aged between 16 and 29 in particular are reporting increased feelings of loneliness.

Koski is confident the campaign will strengthen social ties and prompt people to greet each other more.

In a region where winter means only three hours of sunshine and the average temperature in December hovers around minus 10 degrees Celsius (14 degrees Fahrenheit) in December, there are fewer opportunities for residents to bump into one another on a daily basis.

But Koski said that the modern urban lifestyle is also to blame.

"The bigger the city the more you are by yourself," Koski said, adding that when people lived in villages "we were better at saying these simple things to each other".