Trump "is isolating the US from its most important allies and those allies stood strong in the face of backsliding", Heather Coleman, climate director at Oxfam America, said in a statement referring to the Paris Agreement policy of not weakening climate-related commitments over time.
Leaders from some of the world's most powerful countries issued a joint statement over the weekend, blaming Donald Trump and the United States for the group's failure to reach an agreement on climate change.
"Therefore, we reiterate our commitment to keep our markets open and to fight protectionism, while standing firm against all unfair trade practices", it said, while pledging to help those left behind by globalisation, reported Agence France-Presse.
Trump told leaders at the G7 group of nations in Italy on Saturday that he would make his decision over whether the United States continues to back the climate landmark agreement within the next week.
Under Trump, who once called climate change a "hoax" perpetrated by China and wants to boost the USA coal industry, Washington has resisted intense pressure from its partners to commit to respecting the global 2015 accord on curbing carbon emissions.
German Chancellor Angela Merkel said the discussion on climate change had been "very unsatisfactory", adding "we have a situation of six against one".
Trump on Saturday wrote on Twitter that he would make his final decision next week on whether the US would remain in the climate accord, an worldwide agreement to curb carbon emissions.
After lengthy deliberation, the document did include a separate threat, that was inserted into last year's G-7 statement, to take additional action against Russian Federation, if warranted, for its intervention in Ukraine.
The official said this is based on Trump talking about innovation in clean technology and renewable energy, as well as demonstrating an understanding of climate change. Throughout the campaign, Trump had pledged to withdraw from the pact.
Trump has at times seemed to downplay concerns over climate change.
But the White House said Friday that Trump's view on the topic is "evolving" after hearing other views during the summit. "Here we have a situation of six against one, meaning there is still no sign of whether the USA will remain in the Paris accord or not", she said.
"He came here to get smarter", Cohn said.
Trump has delayed his final decision on the Paris Accord as he wants more time to decide whether the United States should pull out of the 195-nation agreement. At one point this week, the words "Paris Agreement" were almost excluded from the statement, underscoring how contentious the issue became in Taormina, said a Canadian government official who spoke on the condition on anonymity to discuss private deliberations.
Climate Interactive, a team of scientists and computer modelers who track global emissions and pledges, simulated global emissions if every country but the US reaches their individualized goals to curb carbon pollution. On Friday, the Washington Post reported that Trump's son-in-law and senior adviser Jared Kushner spoke with Russia's ambassador to the United States about setting up secret communications with Moscow.
A Canadian government official who spoke to reporters about the 30-minute conversation between Trump and Trudeau on the condition of anonymity said that while the two leaders also spoke about worldwide security, they did not discuss intelligence-sharing.