Climate activists staged protests at airports across Sweden on Sunday, police said, causing brief air traffic delays as they called for the government to stop subsidising the aviation industry.

Activists from the protest group Extinction Rebellion claimed responsibility for the coordinated actions, which took place as the UN COP26 climate conference opened in Glasgow.

Police said 16 people had been arrested at seven airports across the Scandinavian country.

At Stockholm's Arlanda airport, four demonstrators were detained for disruptive behaviour on board two separate aircraft preparing for departure, after being removed from the planes.

The four were suspected of aircraft and airport sabotage, police said.

Among the other protesters was a woman who glued her hands to the runway at the airport in the southern city of Malmo, while four others were arrested for making their way onto the tarmac at the Bromma airport outside Stockholm.

"We have to stop emissions where they can be avoided. That is why we want the state and municipalities to stop subsidising fossil fuel industries, including aviation and airports," Extinction Rebellion said in a statement.