(Close): Weaker commodities and property shares have dragged the FTSE lower, offsetting a rally in banking stocks led by HSBC.
The FTSE 100 index finished the day on 0.2% lower at 6,634.40.
HSBC shares ended 4.5% higher at 504.40p after the bank surprised investors with a $2.5bn share buyback announcement.
That was despite its reporting a 29% fall in pre-tax profits for the six months to the end of June.
The bank described the weak numbers as a “reasonable performance in the face of considerable uncertainty”.
The announcement follows the sale of its Brazilian division last year.
Standard Chartered Bank saw its share price rise 4.2% to 614.30p, despite reporting a 46% fall in pre-tax profits to $1bn (£749m), which it largely attributed to cost-cutting measures amid growing economic uncertainty.
Property-related stocks also fell on lingering concerns about the pace of economic growth in the UK after the country voted in late June to leave the European Union.
Elsewhere, retailer Next reported a rise in overall sales in the three months to the end of July. That led its shares higher by 4.1% to 5,340p.
Next said sales were 0.3% higher compared with a year earlier, although store sales were down 3.3%.
Energy shares were mixed after Ofgem said it would introduce a price cap for energy customers that use pre-pay meters, but stopped short of introducing caps on standard variable energy tariffs.
On the currency markets, the pound was 0.21% lower against the dollar at $1.3328 and 0.23% higher against the euro at €1.19280.