BlackRock chief executive Larry Fink told shareholders in the world’s largest asset manager that “protectionism has returned with force”, days before US President Donald Trump is set to escalate a tariffs war with America’s trading partners.

Fink, whose annual letter is pored over by investors and executives across the corporate world, said his conversations with “nearly every client, nearly every leader” underscored the pervasive unease over the state of the global economy. That anxiety has caused US stock benchmarks to slide since Trump took office.

He said people were “more anxious about the economy than any time in recent memory”. Despite rising participation in the US stock market by everyday investors, “not everyone has shared in this wealth”, he added.