The protesters marched from the US embassy to the British High Commission.
Assange was arrested outside the Ecuadorian Embassy in London earlier this month.
Seven years ago, Assange fled to the embassy and was granted asylum, avoiding extradition to Sweden over a sexual assault case. The case has since been dropped.
However, Ecuador president Lenin Moreno revealed that the nation had withdrawn his asylum after he repeatedly violated international conventions. According to reports, they had removed his access to the internet to stop him engaging in political activities, which is against international law when in asylum.
“No-one should believe the propaganda that Jacinda Ardern’s government is kind and compassionate. Ardern is not ‘anti-Trump’ as the media portrays her. Her government has dramatically strengthened the alliance with Washington,” said leading Socialist Equality Group Tom Peters.
“Freedom to publish, discuss and share information is vital for the working class as it seeks to fight back against austerity and imperialist war. In New Zealand there have been nationwide strikes by doctors, nurses, teachers, and other workers shifting to the left as a result of poverty and inequality.”