The FTSE 100 failed to gain positive momentum on a quiet corporate day amid struggling housebuilding stocks.
The blue-chip index closed 1.3% lower at 6,818.
Housebuilders Taylor Wimpey (TW.) and Barratt (BDEV) slumped by up to 4.1%, while UK supermarkets weakened on news that German discounter Aldi achieved record sales and announced a £300 million investment in its stores.
Tesco (TSCO), Sainsbury's (SBRY) and Morrisons (MRW) were pushed into the red.
West Texas Intermediate (WTI) crude oil advanced 3.5% to $46 and Brent crude oil gained 3.3% to $47.42 per barrel, respectively.
Gold glittered at $1,340 per ounce and copper fell 0.3% to $4,806 per tonne.
BLUE CHIP RISERS AND FALLERS
WPP (WPP) fell 2.5% lower after broker Jeffries International downgraded its rating from hold to buy and cut its price target.
Pharmaceutical firm Shire (SHP) retreated 1.7% following HSBC's downgrade from hold to buy and cut in price target.
MID CAP RISERS AND FALLERS
Scandal-hit Sports Direct (SPD) declined 6% despite an initial positive reaction to Mike Ashley taking over as CEO following Dave Forsey's resignation on Friday.
Broker Peel Hunt's downgrade from add to hold for events company UBM (UBM) accompanied a 2.8% slump in the share price.
SMALL CAP RISERS AND FALLERS
Creative media agency MediaZest (MDZ) was hot off the presses after announcing £250,000 of new business wins since 12 August. Its share price climbed 18.2% to 0.16p.
The market dug Thor Mining (THR) on its confident outlook concerning securing enough money for the Molyhil tungsten project, triggering a share price rise of 20%.
Drug development company Summit Therapeutics (SUMM) received fast track designation from the US Food and Drug Administration for ezutromid in the treatment of Duchenne muscular dystrophy.
Malaysian data centre operator CSF (CSFG) plummeted 51.1% to 0.43p on news it intends to seek shareholder approval to delist from the AIM market.
Oil rig refurbishment specialist Lamprell (LAM) was one of the biggest risers on the London Stock Exchange, rising 11.9% to 71.63p after winning a $90 million contract from new client Master Marine. Lamprell will upgrade its mobile operating unit as an accommodation service vessel for Statoil's Johan Sverdrup field offshore Norway.
Investors were impressed by housebuilder MJ Gleeson's (GLE) 20.5% growth in annual pre-tax profit to £28.2 million and hiked dividend of 45% to 14.5p. The company said trading was 'business as usual' since the EU referendum.
North River Resources (NRRP) fell 18.5% after reporting mixed results at its Namib project, which requires a critical period of assessment to determine how to proceed.
Green gas company Good Energy (GOOD) rose 9.1% to 261.5p following a positive article in The Mail On Sunday.
Brand experience specialist SpaceandPeople (SAL) crashed 34.2% to 26p after swinging from a profit of £62,000 to a £174,000 loss in the first half of the year due to 'subdued trading'. The firm also suspended dividends temporarily.
Respiratory disease-focused drug developer Verona Pharma (VRP) got a shot in the arm following upbeat management expectations for smokers cough treatment RPL554. It also revealed Piers Morgan as chief financial officer, who used to be chief executive of C4X Discovery (C4XD).