Leaders of 78 major companies from around the world urged governments on Monday to include the pricing of carbon emissions in policies to curb global warming, as world leaders prepare for a summit on climate change in Paris next week.

Chief executives of the companies, with combined annual turnover of $2.1 trillion, said in an open letter to world leaders that an ambitious deal in Paris would help create both economic growth and jobs.

The letter said the CEOs, organized by the World Economic Forum, were from companies including HSBC, Siemens, SOHO China, PepsiCo, Engie, Mahindra Group, Tata, Nestlé, BT Group, Unilever and PwC.

“We believe that effective climate policies have to include explicit or implicit prices on carbon achieved via market mechanisms or coherent legislative measures according to national preferences,” they wrote.