President Barack Obama is voicing optimism that this week’s crucial G20 summit will set the framework for recovery, saying that world leaders know they must “deliver a strong message of unity” for the sake of the global economy.

Speaking to the Financial Times on the eve of what some believe will be the most fateful economic summit in decades – but which others dismiss as a talking shop that will do little to halt further global contraction – Mr Obama played down talk of a split between the US and the leading continental European economies, notably Germany and France.