Starting the month on a weak note,stocks worldwide tumbled today as mounting concerns about a possible Greek debt default and global recession fears spooked investors. From Tokyo to London,shares slumped as much as 2 per cent on an average,amid continuing uncertainty over extending bailout for debt-ridden Greece,which has failed to meet its deficit target. Dragged by banking stocks,European bourses took a severe beating in afternoon trade even as finance ministers from eurozone are expected to meet later in the day to discuss Greek turmoil. Most of the Asian markets closed deep in red,with Hong Kong's Hang Seng index leading the rout. The index crashed over four per cent to close at 16,822.20 points. Against the backdrop of jittery business sentiment and slowing industrial activity,Japanese benchmark Nikkei 225 slid about two per cent to 8,545.48 points. India's key 30-share index Sensex declined around two per cent to 16,151.50 points while Australia's S&P/ASX 200 Index fell nearly three per cent to 3,897 points. Apart from persisting European debt crisis,sluggish industrial activity in emerging and developed markets have fuelled fears of the world economy skidding into recession. In Europe,Germany's Dax index plunged over two per cent to 5,374.81 points. The two other key indices - UK's FTSE 100 and France's Cac 40 - plummeted more than two per cent to 5,043.26 points and 2,922.01 points,respectively. Going by reports,Greece this year expects to have a deficit of 8.5 per cent of the national GDP,which is way above the target of 7.6 per cent set by International Monetary Fund and European Union. This scenario could hamper ongoing international bailout efforts. Meanwhile,euro fell against the US dollar and Japanese yen in the wake of slow progress in European rescue efforts. Gold prices rose as investors scrambled for safe havens amid escalating economic uncertainties and volatile equity markets.