Greens Leader Christine Milne has proposed further actions in response to the Bali Nine executions and says the Australian Parliament must demonstrate its cross-party opposition to the death penalty with better safeguards to protect Australian citizens from state-sanctioned execution overseas.

"What happened to Myuran Sukumaran, Andrew Chan and other Australians before them must not happen again. We have a responsibility to do all we can to oppose the death penalty and protect people from it, wherever it exists," said Senator Milne.

On behalf of the Australian Greens I express my deepest sympathies to the families and friends of Andrew Chan, Myuran Sukumaran, and the six other people who have been executed in Indonesia overnight.

Myuran and Andrew will be remembered for overcoming their past to live meaningful lives, even from prison, not just for the way they died.

Their actions over the past ten years were testament to their remorse, and have given many of their fellow prisoners an opportunity to live better lives.

It is a tragedy Andrew and Myuran were denied their own second chance.

Australian Greens Leader Christine Milne says further, urgent efforts must be made to save Australians Andrew Chan and Mayuran Sukumaran from execution in Indonesia, and changes are needed to ensure their situation is not repeated.

"I'm calling on Foreign Minister Julie Bishop to make one last trip to Indonesia to try to intervene on behalf of these men, who have now been told they will be killed within three weeks," said Senator Milne.

"Let's not talk about the ‘fate' of these men while we may still have the power to change it.