The UK blue chip FTSE 100 <.FTSE> index rose 0.2 percent at 7,529.72 points, while mid caps <.FTMC> were flat.
Among consumer stocks that added most points to the FTSE were Unilever (>> Unilever) and British American Tobacco (>> British American Tobacco), up 1.4 and 2 percent respectively, while gains in oil major Royal Dutch Shell <RDSa.L> and miner Rio Tinto (>> Rio Tinto) also helped.
Paper and packaging firm Mondi (>> Mondi) rose 2.3 percent after Morgan Stanley moved its rating on the firm to "overweight" from "equal weight".
Shares in housebuilder Persimmon (>> Persimmon) fell 3.5 percent, the worst-performing on the FTSE 100, after it issued a disappointing trading statement.
Persimmon depressed the whole sector, with Barratt Development (>> Barratt Developments), Taylor Wimpey (>> Taylor Wimpey), Bovis Homes (>> Bovis Homes Group), Crest Nicholson (>> Crest Nicholson Holdings PLC) and Redrow (>> Redrow plc) also falling.
"We continue to see stiffening headwinds for the housebuilders from a softening market climate with a much weaker pricing outlook, rising costs and a loss of confidence in pricing by both buyers and estate agents," Shore Capital analysts said.
Shares in Marks & Spencer (>> Marks & Spencer Group) rose 1.6 percent at the end of a volatile session after the grocer reported results.
The company posted a lower-than-expected fall in first-half profit and said it would accelerate its turnaround plan and open fewer Simply Food stores than previously planned.
"You've got a slightly weaker UK consumer possibly coming through in one or two of the retailers' results," Hargreaves Lansdown analyst George Salmon said, adding that upcoming results from Halfords (>> Halfords Group plc) and Sainsbury (>> J Sainsbury) would shed more light on this theme.
Shares in utility SSE (>> Scottish and Southern Energy) slipped 0.8 percent after agreeing to merge its UK retail activities with German energy group Innogy (>> Innogy SE).
SSE also reported half-year figures, which included an 8 percent drop in profit due to weakness in its networks business.
Some analysts were cautious about the merger announcement.
"Although the idea of a spin-off is understandable, we highlight that both businesses vary significantly in outlook and the industry's track record in integrating service and billing systems is poor," analysts at Jefferies said in a note.
"The move could also result in a rebasing of SSE's dividend and impairment for Innogy."
Outside of large caps, Wizz Air (>> Wizz Air Holdings PLC) dropped 9.3 percent after reporting results, with the focus on concerns over ticket pricing trends.
Wizz Air's CEO also said it was interested in acquiring airport slots at London Luton from failed airline Monarch.
(Reporting by Kit Rees; Editing by Raissa Kasolowsky/Mark Heinrich)
By Kit Rees and Danilo Masoni
Stocks treated in this article : Spectra Energy Corp.
, Scottish and Southern Energy
, British American Tobacco
, Taylor Wimpey
, Barratt Developments
, Marks & Spencer Group
, Redrow plc
, Bovis Homes Group
, J Sainsbury
, Rio Tinto
, Halfords Group plc
, Crest Nicholson Holdings PLC
, Wizz Air Holdings PLC
, Innogy SE
, Sea Ltd (ADR)