The United Nations has defended its decision to block Prime Minister Scott Morrison from speaking at a climate summit this weekend. 

British Prime Minister Boris Johnson, who is hosting the conference alongside the UN, invited Miorrison to speak at the summit weeks ago but reneged the offer this week over whether Australia’s climate change policies were sufficient to warrant a spot speaking. 

Morrison had planned to announce during the speech that Australia would drop its controversial plan to use Kyoto carryover credits to achieve its 2030 emissions reductions targets. 

Special adviser to the UN secretary-general, Selwin Hart, said Australia had not met the requirements to speak.