For the three last quarters, UK firms have run down their inventories. In fact, the run down during the second quarter of 2009 was the largest quarterly percent decline in fifty years.
Firms can not continue to run down their stocks for ever. During every recession, businesses tend to overdo it and "over empty" their warehouses, creating shortages. The UK economy is probably close to that point right now. Firms will soon start to replenish stocks creating a temporary boost in GDP growth.