European shares surged and the Greek stock market jumped 8% while the borrowing costs of Italy, Spain, and Portugal — the countries most likely to be hit if Greece heads for the eurozone exit — fell sharply.

Worries about the outlook for growth in China and a slide in the price of oil pushed the stock market to its biggest loss in almost seven weeks today.

The US stock market returned to record levels yesterday as investors regained their appetite for riskier stocks.