George Osborne's austerity budget will cause 1.3m job losses over the next five years according to Treasury figures.
The Office for National Statistics will postpone its next release of data on economic growth, in an highly unusual move for the official statistician.
The amount raised by companies from equity capital markets during the first half of the year was the lowest in five years.
Updated 15.00 UK time: The FTSE 100 is down 3.05%, or 154 points, to 4917 as concerns about the Chinese economy weigh heavily on investor minds.
BP has denied reports from Russia that Tony Hayward is set to stand down.
China has set the renminbi-dollar exchange rate at its highest level in five years, after announcing it would make its currency more flexible.
The financial services industry grew at the fastest rate since Northern Rock collapsed in the last three months - but the "modest pick-up" in activity was lower than expected.
The FTSE 100 has opened in positive territory as investors react with relief to a watered down US financial services reform bill.
UK banks could be under further pressure to curb lending after the G20 drafted rules to force them to bolster balance sheets by as much as £130bn.
The US Congress is finally close to completing the largest policy reform of the financial sector since the 1930s.