The agreement is a protocol to the United Nations Framework Convention on Climate Change (UNFCCC), which was adopted at the 1992 Earth Summit in Rio de Janeiro and did not establish legally binding restrictions on emissions or enforcement mechanisms. Only Parties to the UNFCCC may become Parties to the Kyoto Protocol. The Kyoto Protocol was adopted at the third meeting of the Conference of the Parties to the UNFCCC (COP 3) in Kyoto, Japan, in 1997. On 12 December 2015, the text of the Paris Agreement was adopted, a legally binding pact containing all the elements necessary for the development of a comprehensive climate change strategy for the post-2020 period – the period before 2020 falls under the second phase of the Kyoto Protocol (the Doha Amendment). Some of the key points are summarized below: the Protocol left open several issues that would later be decided by the Sixth COP6 Conference of the Parties to the UNFCCC, which attempted to resolve these issues at its meeting in The Hague in late 2000, but could not reach an agreement due to disputes between the European Union (which advocated stricter implementation) and the United States. Canada, Japan and Australia (who wanted the agreement to be less demanding and more flexible). On August 4, 2017, the Trump administration issued an official notice to the United Nations that the United States intended to withdraw from the Paris Agreement as soon as it was legally authorized to do so.  The call for withdrawal could only be submitted after the agreement for the United States was in force for 3 years on November 4, 2019.   Am 4. In November 2019, the U.S. government filed the withdrawal notification with the United Nations Secretary-General, depositary of the agreement, and formally withdrew from the Paris Climate Agreement a year later, when the withdrawal entered into force.
 After the November 2020 election, President-elect Joe Biden promised to reintroduce the United States into the Paris Agreement by his first day in office and renew America`s commitment to mitigating climate change.   Gupta et al. (2007) evaluated the climate policy literature. They noted that there was no authoritative assessment of the UNFCCC or its protocol that these agreements were or would succeed in solving the climate problem.  These assessments assumed that the UNFCCC or its protocol would not be amended. The Framework Convention and its Protocol contain provisions for future policy measures. Another area that was discussed was the role of Kyoto flexibility mechanisms – emissions trading, joint implementation and the Clean Development Mechanism (CDM).   Flexibility mechanisms have received both positive and negative feedback.
   The Protocol is based on the principle of common but differentiated responsibilities: it recognizes that each country has different capacities in the fight against climate change due to economic development and therefore obliges developed countries to reduce current emissions on the basis that they are historically responsible for current greenhouse gases in the atmosphere. .