"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 added.
The senior official said that Trump's fellow leaders had stressed their view that the Paris accord was not only about protecting the environment, but also served the business interests of the USA and its G7 partners.
During the campaign he had threatened unilateral tariffs on Mexican and Chinese goods and said he would quit the North American Free Trade Agreement unless it is renegotiated to his liking.
Axios said the decision, if true, would unravel predecessor Barack Obama's climate policies and send a "combative signal" to the rest of the world that global warming isn't one of Trump's priorities. But the failure of the U.S.to reduce its greenhouse gas emissions, being the world's second highest producer of such pollution, will worsen and likely accelerate an already risky problem.
The leaders found agreement on other points, such as backing closer co-operation against terrorism after the concert bombing Monday in Manchester that killed 22 people.
Trump and Trudeau also discussed "issues of global concern".
He also pointed to a quote from Malcolm Turnbull from November past year, when Turnbull was asked if Australia would remain in the Paris agreement if then president-elect Trump followed through on his threat to cancel the emissions reductions commitments made by Barack Obama in December 2015.More news: Jared Kushner considered secret back channel to talk to Russia, reports say
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Trump said that he's waiting for the analysis of the steel and aluminum industries that the US Department of Commerce plans to publish in June.
Some supporters of the agreement have suggested that a withdrawal by the US would help position China as a leader of global environmental policy, and new green technologies.
Leaders from the G-7 countries were expected to gather at the San Domenico Palace Hotel on Saturday morning. "President Trump should now return to Washington and make the right decision, take climate change seriously and take action with the rest of the world".
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. If other countries follow the US out of the Agreement, which remains a risk, that danger only multiplies.
The source adds that G-7 members were still wrestling over a statement on trade and whether it would condemn protectionism, as previous group statements have.