Only two countries refused to participate in the Paris Agreement, the historic climate agreement to reduce greenhouse gas emissions signed by almost all countries. One of them, Syria, is in ruins after six years of protracted civil war. The other, Nicaragua, boycotted the deal in protest at its initial unambitious targets and its failure to legally link countries to their emissions targets. Among other things, countries must report on their greenhouse gas inventories and progress towards their targets so that external experts can assess their success. Countries should also reconsider their commitments by 2020 and set new targets every five years, with the aim of further reducing emissions. They must participate in a “global stocktaking” to measure collective efforts to achieve the long-term goals of the Paris Agreement. In the meantime, developed countries must also estimate the amount of financial assistance they will provide to developing countries to help them reduce their emissions and adapt to the effects of climate change. President Trump is pulling us out of the Paris Climate Agreement. On June 1, 2017, U.S. President Donald Trump announced that the United States would withdraw from the agreement.  According to Article 28, the earliest possible effective withdrawal date for the United States is November 4, 2020, with the agreement having entered into force in the United States on November 4, 2016. If it had chosen to withdraw from the UNFCCC, it could be notified immediately (the UNFCCC entered into force for the United States in 1994) and enter into force a year later.
The 4. In August 2017, the Trump administration sent an official notice to the United Nations stating that the United States intended to withdraw from the Paris Agreement as soon as it was legally allowed to do so.  The formal resignation could not be submitted until the agreement was in force for the United States for 3 years in 2019.   The level of NDCs set by each country will set that country`s objectives. However, the “contributions” themselves are not binding under international law because they do not have the specificity, normative character [clarification required] or mandatory language required to create binding norms.  In addition, there will be no mechanism that requires a country to set a target in its NDC by a certain date, and no application if a set target is not achieved in an NDC.   There will be only one “Name and Shame” system or like János Pásztor, the UN. The Under-Secretary-General for Climate Change told CBS News (USA) a “Nominate and Encourage” plan.
 Given that the agreement does not foresee any consequences if countries do not comply with their obligations, such a consensus is fragile. A net of nations withdrawing from the deal could trigger the withdrawal of more governments and lead to a total collapse of the deal.  To date, 195 countries have signed the agreement, and two have ratified it without first signing it. This means that all members have acceded to the United Nations Framework Convention on Climate Change. These include all members of the United Nations, the State of Palestine, Niue and the Cook Islands, as well as the European Union. The agreement contains commitments from all countries to reduce their emissions and work together to adapt to the effects of climate change and calls on countries to strengthen their commitments over time. The agreement provides an opportunity for developed countries to assist developing countries in their mitigation and adaptation efforts, while providing a framework for transparent monitoring and reporting on countries` climate goals. A preliminary study with inventory implications was published in April 2020 in Nature Communications. Based on a public policy database and multi-model scenario analysis, the authors showed that the implementation of current policies leaves a median emissions gap of 22.4 to 28.2 GtCO2eq by 2030 with optimal trajectories to achieve the Paris targets well below 2°C and 1.5°C.
If nationally determined contributions were fully implemented, this gap would be reduced by one third. It was found that the countries assessed had not achieved the promised contributions with the implemented policy (implementation gap) or that they had an ambition deficit with optimal trajectories well below 2°C. The protocol, which only entered into force in 2005, set binding emission reduction targets only for developed countries, based on the assumption that they were responsible for most of the Earth`s high greenhouse gas emissions. The United States first signed the agreement, but never ratified it; President George W. Bush argued that the deal would hurt the U.S. economy because it would not include developing countries such as China and India. Without the participation of these three countries, the effectiveness of the treaty proved limited, as its objectives covered only a small fraction of total global emissions. The agreement stipulated that it would only enter into force (and thus become fully effective) if 55 countries producing at least 55% of global greenhouse gas emissions (according to a list drawn up in 2015) ratified, accepted, approved or acceded to the convention.
  On April 1, 2016, the United States and China, which together account for nearly 40% of global emissions, issued a joint statement confirming that the two countries will sign the Paris Climate Agreement.   175 Contracting Parties (174 States and the European Union) signed the Agreement on the day of its first opening for signature.   On the same day, more than 20 countries published a memorandum of understanding to accede as soon as possible in order to accede in 2016. With its ratification by the European Union, the agreement received enough contracting parties to enter into force on 4 November 2016. Despite Trump`s campaign promises, the White House was under intense pressure to stay in the Paris Agreement. Secretary of State Rex Tillerson, Energy Secretary Rick Perry, adviser and first daughter Ivanka Trump and her husband, Adviser Jared Kushner, support keeping the deal going, albeit with some adjustments to the emissions target. Major companies, including oil giant Exxon Mobil Corp., have also warned Trump against cancelling the deal. As of November 2020, 194 states and the European Union had signed the agreement. 187 countries and the EU, which account for about 79% of global greenhouse gas emissions, have ratified or acceded to the Convention, including China and India, the countries with the 1st and 3rd largest CO2 emissions among UNFCCC members.
   As of November 2020[update], the United States, Iran and Turkey are the only countries with a share of more than 1% of global emissions that are not contracting parties. Niklas Höhne, a climate scientist and founder of the New Climate Institute in Germany, said Turkey “stands out” among the list of countries that have not yet ratified the agreement. In 1992, President George H.W. Bush joined 107 other heads of state at the Earth Summit in Rio, Brazil, to adopt a series of environmental agreements, including the UNFCCC framework, which is still in force today. .