John McDonnell has promised to ­pursue the overthrow of capitalism and legislate to force private companies to share profits if he becomes chancellor.

The close ally of Jeremy Corbyn said he wants to transform society “in a way that radically changes the system”.

Asked if his job was now the overthrow of capitalism, the shadow chancellor replied: “Yes it is. It’s transforming the economy.” Pressed on whether there is a difference between transforming the economy and overthrowing capitalism, he said: “I don’t think there is . . . I want a socialist society.”

When asked by the BBC what he would do to privately-owned business, Mr McDonnell replied: “We’d follow France’s example, they legislate for profit sharing. We’d expect companies to profit share as well