Which International Treaty is related to Ozone Layer Protection?

Which International Treaty is related to Ozone Layer Protection?

کون سا بین الاقوامی معاہدہ اوزون کی تہہ کے تحفظ سے متعلق ہے؟
Explanation

 Montreal Protocol is an international treaty designed to protect the ozone layer, agreed on 16 September 1987, and entered into force on 1 January 1989.