After a positive start, the FTSE 100 has reversed its gains in a directionless market.
An hour into trade, the blue-chip index is about a fifth of a percent up at 8,777.
J Sainsbury PLC (LSE:SBRY) is topping the early leaderboard after a solid trading update. The supermarket chain reported a 4.9% increase in total sales in the first 16 weeks of its financial year, with grocery sales rising 5%.
Aviva also trading higher after the Competition & Markets Authority cleared its acquisition of Direct Line Insurance Group plc.
Shares of packaging group Mpac Group (LSE:MPAC) are down sharply after it warned on profits after a "material" slowdown in order intake in the second quarter, particularly in North America, which resulted in management taking various steps, including closing one US facility and other actions to reduce debt.
Food wholesaler Kitwave Group PLC (AIM:KITW) has also plunged after it released interim results, with fragile consumer confidence hitting its outlook.