Major industrialised economies will suffer the worst slump since the 1930s, according to new research from Deutsche Bank.

The warning underlines the fact that policymakers have failed to prevent the financial crisis from turning into a full-blown economic slump. It comes as world leaders agreed to hold a summit in New York billed as the "Bretton Woods meeting for the 21st century".

In its major assessment of the global economy's health, Deutsche Bank also warned that Britain is even more vulnerable than the US or the euro area, as it predicted that the powerhouses of India and China would fail to support the wider global economy through the downturn.

The banks' economists Thomas Mayer and Peter Hooper said: "We now expect a major recession for the world economy over the year ahead, with growth in the industrial countries falling to its lowest level since the Great Depression and global growth falling to 1.2pc, its lowest level since the severe downturn of the early 1980s."