The announcement deals a major blow to worldwide efforts to combat global warming and also distances the USA from its closest allies overseas.
He added: "Fighting climate change is a global consensus, it's not invented by China. and we realize that this is a global consensus agreement and that as a big developing nation we should shoulder our worldwide responsibility". He said that his decision was "a reassertion of America's sovereignty".
"The journey from Paris is well underway", Guterres said.
A withdrawal would put the United States in the same camp as Nicaragua and Syria: a tiny group of countries refusing to participate in the nearly universally supported Paris climate change agreement. "If we can't, that's fine", he said.
Guterres said to the audience in NY on Tuesday that "it would be important for the USA not to leave the Paris agreement", but added if the country did, then Americans needed "to remain engaged".
"These countries are committed", he said.
"India makes its participation on receiving billions and billions of dollars from developed countries". Paris accord is very unfair at the highest level to the United States.
"The loss of US finance would be the biggest headache, and of course the symbolism is not good", said Michael Grubb, a professor at University College London who has advised the European Union on climate policy. "If we can, great".
Without mentioning the USA specifically, he said China has been "actively promoting the Paris agreement and we were one of the first countries to ratify the Paris agreement". That means the USA would remain in the agreement, at least formally, for another three-and-a-half years till 2020, ensuring the issue remains alive in the next presidential election.
Abandoning the pact was one of Trump's principal campaign pledges.
The White House did not confirm those reports and it was unclear whether Trump would fully scrap United States participation or merely water down USA emissions objectives. The U.S. has agreed to reduce its emissions by 2025 to 26 per cent to 28 per cent of 2005 levels - about 1.6 billion tons.
The president is also facing intense 11th-hour lobbying from both inside and outside the administration to keep the United States as part of the accord.
In addition to the USA, only two other countries - Syria and Nicaragua - are not part of the Paris agreement.
The EU official involved in organizing the EU-China meeting said it would will "send important signals for the multinational system", as Trump moves to unpick some of the global trade agreements the USA has signed up to.
"We deem the momentum generated in Paris in December 2015 irreversible, and we firmly believe that the Paris Agreement can not be renegotiated, since it is a vital instrument for our planet, societies and economies", wrote French President Emmanuel Macron, German Chancellor Angela Merkel and Italian Premier Paolo Gentiloni. Major oil producers are also looking to the future and diversifying their economies and even Saudi Arabia has announced plans to install 700 megawatts of solar and wind power, he said.
In Germany, a statement issued by seven Social Democratic ministers in Merkel's coalition government said the United States "is harming itself, we Europeans and all the people of the world".
Responding to Trump's pointing to his city, Pittsburgh Mayor Bill Peduto called the decision "disastrous for our planet, for cities such as Pittsburgh", and a step that "has made America weaker and the world less safe".
Scientific data confirms that climate change is real and the only way we can move forward, as a nation and world, is to make the admission and address the threat to our environment, air, land, health and way of life.
Congressional Republicans applauded the decision, with Senate Majority Leader Mitch McConnell of Kentucky saying Trump had "put families and jobs ahead of left-wing ideology and should be commended".
Guterres said countries can either "get on board or get left behind" when it comes to taking action on global warming because they will miss out on new economic opportunities from greener industries.
Former Obama aide David Axelrod said "in backing off of climate pact", Trump "is locking arms with Syria and Nicaragua and matching confidently into the past".
Conservatives, such as Pruitt, have argued that the agreement is not fair to the United States and that staying in it would be used as a legal weapon by environmental groups seeking to fight Trump environmental policies. "The falling cost of renewables is one of the most encouraging stories on the planet today", he said.
The United States, one of the biggest greenhouse emitters in the world, would announce its position this week whether to leave the deal or to stay.
The White House had previously indicated that Trump could simply recalibrate emissions targets. But Trump's statement was clear and direct.