Canada, the European Union and China have said they will honor their commitments to the pact, with the United States or without it. Indian Prime Minister Narendra Modi met Spain's Mariano Rajoy in Madrid on Wednesday, and both countries reaffirmed their Paris commitments, without mentioning the United States.
The drive to improve efficiency has prompted many U.S. business leaders to support the Paris accord. In April, the chief executives of 16 big U.S. corporations, including Apple and Wal-Mart, wrote the White House urging Trump to support the Paris treaty.
They argued that U.S. participation would make American companies more competitive, create jobs and reduce the risks of future climate-related damage.
Fossil fuel producers including Exxon Mobil, BP and Shell have also said the United States should abide by the deal.
—Reuters and AP contributed to this report
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