Leaders of major companies, including several chemical producers, have published an open letter in business newspaper Wall Street Journal urging US President Donald Trump not to pull out of the Paris Agreement on climate change.

CEOs such as Andrew Liveris of Dow Chemical and Ed Breen of DuPont, joined others from the technology, automotive and banking sectors to express their strong support for keeping the US in the treaty, which went into effect in November 2016 in a bid to cut greenhouse gas emissions and limit global warming.

“We are committed to working with you to create jobs and boost US competitiveness, and we believe this can be best achieved by remaining in the Paris Agreement,” they wrote. “We believe there is strong potential for negative trade implications if the US exits from the Paris Agreement.”  The industry leaders believe the treaty will benefit US manufacturing by encouraging companies to modernize to more efficient technologies.

During his presidential campaign, Trump described climate change as a “hoax” and threatened to overturn Obama’s clean air legislation and withdraw from the Paris accord. His administration already has taken steps to kill the former, with no protests from industry ensuing.

The letter follows a petition signed in January by more than 350 companies, either headquartered or with operations in the US, to uphold the country’s commitment to the goals of the climate deal. They said this would give clarity to financial decision-makers and boost investors’ confidence.