(AFP) - Swedish climate campaigner Greta Thunberg was fined on Monday for disobeying police at a rally last month, but said she acted out of necessity due to the climate crisis.

The 20-year-old appeared in court in the southern Swedish city of Malmo after 11 am (0900 GMT) on Monday, without responding to questions from reporters.

The activist "took part in a demonstration that disrupted traffic" and "refused to obey police orders to leave the site", according to the charge sheet seen by AFP.

"It's correct that I was at that place on that day, and it's correct that I received an order that I didn't listen to, but I want to deny the crime," Thunberg told the court when asked about the charge against her.

Thunberg said she had acted out of necessity, citing the need created by the "climate crisis."

After a short trial, the court nonetheless found that she was still liable for her actions and sentenced her to pay a fine of 1,500 kronor ($144) plus an additional 1,000 kronor to the Swedish fund for victims of crime.

The rally, organised by environmental activist group "Ta tillbaka framtiden" (Reclaim the Future), tried to block the entrance and exit to the Malmo harbour to protest against the use of fossil fuel.

"We choose to not be bystanders, and instead physically stop the fossil fuel infrastructure. We are reclaiming the future," Thunberg said in an Instagram post at the time.

Thunberg shot to global fame after starting her "School Strike for the Climate" in front of Sweden's parliament in Stockholm at the age of 15.

She and a small band of youths founded the Fridays for Future movement, which quickly became a global phenomenon.

- 'Burning our lives' -

In addition to her climate strikes, the young activist regularly lambasts governments and politicians for not properly addressing climate issues.

Reclaim the Future insists that despite the legal pressures, it remains unbowed in its determination to stand up to the fossil fuels industry.

"If the court chooses to see our action as a crime it may do so, but we know we have the right to live and the fossil fuels industry stands in the way of that," group spokesperson Irma Kjellstrom told AFP.

Six members of the organisation would be appearing in court in Malmo, she said.

"We young people are not going to wait but will do what we can to stop this industry which is burning our lives," she said, explaining the group's plans for continuing civil disobedience.

© Agence France-Presse