Online recruitment has fallen for the fourth consecutive month, according to the Monster Employment Index.
The index fell in September to its lowest level since April 2007.
Online hiring for staff across all occupational groups declined for the second month in a row. Banking, finance and the insurance sector have all experienced sharp declines in job availability, while online recruitment in HR has fallen to a two-year low.
However, there were moderate increases in availability in public sector, defence and community and legal positions.
Hugo Sellert, head of economic research at Monster Worldwide, said: "The latest index findings suggest that overall job losses are likely to intensify as the troubled financial and housing industries continue to drag down the wider UK economy.
"However, while the private sector is growing ever more cautious about adding staff, once again the public sector is showing that it less affected by a struggling economy."
The Monster Employment Index is a monthly analysis of millions of online job opportunities from a selection of corporate career sites and jobs boards across the UK, including Monster.co.uk. The European index has a baseline of 100, which is the average level of online job availability measured during the first 12 months of data collection when the index first began (November 2004 - October 2005).
The index measures monthly online job demand by analysing the change in online job posting activity each month.