Climate change protest blocks Melbourne bridge, stops trams

Police arrested 36 people after hundreds of climate change demonstrators blocked a bridge in the Melbourne CBD and caused major disruptions to traffic and trams.

Two groups of protesters, many from the Extinction Rebellion group, walked across the Princes Bridge, halting traffic at either end as part of a three-hour stand-off.

Police warned the protesters they would use "reasonable force" to move them on.

Officers were seen lifting them up from the street and carrying them away.

Victorian Police said in a statement 36 were arrested.

"Protestors assembled on the bridge and were asked by police to move off the roadway," it said.

"A number of protestors complied but police had to arrest 36 protestors who refused to leave the roadway. They are expected to be charged on summons for obstructing a roadway."

Public Transport Victoria (PTV) said on its website eight tram routes along Swanston Street and St Kilda Road were affected by the protest on the Princes Bridge.

Commuters were advised to use trains as an alternative.

Extinction Rebellion said on its website the protest would "draw attention to the climate and ecological emergency we are facing".

It is the second Melbourne climate rally ahead of what the group is calling the international "Spring Uprising" on October 7, when protests are planned around the world.

Hundreds of people have also rallied in Melbourne calling for more rights for refugees and an end to discrimination.

Former refugee footballer Hakeem Al-Araibi has called on the prime minister to help others like him at the protest.

The Bahrain-born 25-year-old has travelled a rocky road, including a stint in a Bangkok jail, to realise his dream of a life in Australia.

Other attendees included federal politicians Ged Kearney from Labor and Greens leader Richard Di Natale.

With AAP