Donald Trump may have turned his back on the Paris Climate Agreement, but a huge number of tech firms, including Google, Facebook, Apple, and Amazon, have signed an open letter pledging their support for climate action that meets the targets set out by the accord.

The coalition, called “We are still in,” consists of over 1200 companies, educational institutions, mayors, governors, states, and investors. Most of the big Silicon Valley names have signed up, though Oracle and IBM are conspicuously absent [update: IBM has now signed up]. Unlike Elon Musk, IBM CEO Ginni Rometty decided to remain on Trump’s business advisory council following the US withdrawal.

The group says its members will remain actively involved with the international community as it looks to reduce greenhouse gas emissions and stop the planet from warming more than 1.5 degrees Celsius (about 3.6 degrees Fahrenheit) above preindustrial levels. It also wants to accelerate the transition to clean, renewable energy.

“In the U.S., it is local and state governments, along with businesses, that are primarily responsible for the dramatic decrease in greenhouse gas emissions in recent years.” the letter reads. "Actions by each group will multiply and accelerate in the years ahead, no matter what policies Washington may adopt," they wrote.

The US is the only country ever to have left the Paris Agreement – Nicaragua and Syria never signed up in the first place.

The statement was coordinated by a number of organizations, including the World Wildlife Fund, the Center for American Progress, and Michael Bloomberg’s Bloomberg Philanthropies, which has also promised up to $15 million to help support the Agreement following the US’ exit.