Shares on the Athens Stock Exchange are suffering huge losses of over 22 per cent after the market reopened for the first time in more than a month.

Greece is currently locked in intense negotiations with bailout lenders in an effort to negotiate the terms of a massive new rescue package in the next two weeks.

The main index plunged early today after the country's Capital Market Commission formally approved the reopening of the exchange.

The exchange and Greek banks were closed on June 29, when controls on money withdrawals and transfers were imposed to prevent a collapse in the banking system due to a run on deposits.

Banks have since reopened, while maintaining strict withdrawal limits.

Greek bank stocks suffered the most, hitting or nearing the daily trading limit of a 30% loss.

Markets in the rest of Europe, however, were largely unaffected.

Greece is expected to head back into recession in 2015 - after briefly emerging from a six-year contraction - due to the effects of capital controls and months of uncertainty over the country's future in the euro.

A monthly survey of business and consumer confidence, the Economic Sentiment Indicator, fell for a fifth consecutive month in July to its worst level since October 2012.

"The negative development is the result of the sharp deterioration in business expectations in all areas, but also a recent and significant decline in consumer confidence," said the Foundation for Economic and Industrial Research, which conducts the survey.

Greece needs to complete the bailout talks and get more loans before August 20, when it has a repayment to make worth more than €3 billion to the European Central Bank.