The legislation mandates that the country should produce no greenhouse gases except methane by 2050.
In the most serious scandal Ardern has faced since she took office in late 2017, the leader admitted 'mistakes were made' after a Labour Party volunteer accused a senior party staffer of assault.
Greenpeace campaigner Joseph Moeono-Kolio said Morrison's government appeared intent on watering down the summit's communique, due to be issued on Thursday.
The cover features 15 women, including teenage climate activist Greta Thunberg and New Zealand Prime Minister Jacinda Ardern, who through their work have contributed to changing the world.
Prime Minister Theresa May thanked the England team for winning the showpiece and ending a 44-year wait.