Mark Zuckerberg, Facebook chief executive, warned the world against turning inwards, including building walls, blocking free expression and reducing trade and immigration, in his most politically charged speech to date.

Speaking at Facebook’s annual developer conference in San Francisco, Mr Zuckerberg said the path was to connect more, not less, and to prioritise “hope over fear”. He lashed out against isolationists, in comments that could be read as criticism of US presidential candidate Donald Trump, who has a controversial plan to build a wall along the border with Mexico.

“We are one global community,” he said. “Whether we are welcoming a refugee fleeing war or an immigrant seeking opportunity, coming together to fight a global disease like Ebola or to address climate change.”