Climate protesters blocked traffic on Kings Avenue Bridge on Wednesday evening, after assembling in front of the Department of Agriculture, Water and Environment in Canberra.
It follows Tuesday protests that blocked the corner of Marcus Clarke and Barry Drive in Civic.
As of 5pm, about 50 people had gathered for the rally and police were attending at Kings Avenue Bridge, a spokesperson for Extinction Rebellion said.
Among protesters is 77-year-old Nick Abel, an honorary CSIRO fellow and honorary ANU associate professor.
"I'm enraged about the dangerous future my generation is leaving for humans and nature, and I'm here to help change that," Mr Abel said in a statement.
"Environment Minister Susan Ley's appeal against the court decision that the Australian government has a duty of care to young people is an open declaration of this callous negligence."
The rally will focus on Ms Ley's appeal against a federal court ruling that the government has a duty of care to protect Australian children from climate change.
"We're going to hold the department to account for Sussan Ley's decision, because our government is failing to protect us and we have a duty to rebel," an Extinction Rebellion's spokesperson said.
An ACT police spokesperson said there had been two people charged Wednesday with defacing public property, in relation to Extinction Rebellion protests.
An Extinction Rebellion spokesperson said there had been five arrests throughout the protest.