The FTSE 100 Index failed to make headway today as a surprise fall in retail sales weighed on sentiment.
Trading was also lacklustre on America's Dow Jones Industrial Average as investors received mixed economic data.
The Footsie closed 15.4 points lower at 5540.1, with the Dow down by a similar amount.
News that US lenders repossessed more homes in August than in any month since the sub-prime mortgage crisis hit Wall Street, overshadowing figures showing a fall in US jobless claims.
In the UK, a shock fall in retail sales weighed on stocks.
The 0.5% decline for August sales offset initial encouragement seen after B&Q owner Kingfisher beat market forecasts with a 23% rise in half-year profits.
Kingfisher clung to positive territory after initially rising 3%, but the rest of the sector saw declines.
The top flight hit a four-month high at the start of the week, however it has been stuck in a narrow trading range since then as investors struggle to make up their minds on the next move for world markets.
Today's downbeat retail sales also put pressure on sterling, with the pound down to $1.56 and €1.19.
Oil and commodity stocks did their best to keep the FTSE 100 on an even keel after BP rose 4.4p to 408.5p, Royal Dutch Shell lifted 21.5p to 1829p and Randgold Resources cheered 50p to 6295p.
Among retailers reeling from the Office for National Statistics retail data, Next shares, which rose 7% on Wednesday, slipped 6p to 2170p, while Marks & Spencer surrendered an early gain to stand 3.5p lower at 376.1p.
Kingfisher remained in positive territory, up 0.9p to 219.8p, after the company's half-year figures impressed investors, despite continued pressure on sales in the UK division.
Homebase rival Home Retail Group was down 1.1p to 213.4p, while Kesa Electricals lifted 2.1p to 137.5p in the FTSE 250 Index after reporting strong first quarter sales from its Comet business in the UK.
One of the biggest falls in the top flight came from BT Group after Morgan Stanley downgraded the stock on fears the pensions regulator may accelerate the company's proposed deficit reduction schedule. The stock fell 3% or 4.4p to 140p.
Outside the top flight, attention was focused on the dairies sector after Robert Wiseman revealed a major profits squeeze as it battles "intense" competition across the industry.
The Glasgow-based firm, which processes and delivers more than 30% of the fresh milk consumed in Britain every day, warned its profits could be as much as £16m (€19.12m) lower in the next financial year due to pressure on margins.
Shares slumped 30% or 143.5p to 342p and caused rival Dairy Crest to fall by 4% or 14.5p to 361.3p.
The biggest Footsie risers were Cable & Wireless ahead 3.4p to 77.6p, Eurasian Natural Resources up 32p to 898p, Aggreko up 22p to 1550p and Royal Dutch Shell up 21.5p to 1829p.
The biggest Footsie fallers were Icap down 17.1p to 437.6p, BAE Systems down 11p to 329.8p, BT Group off 4.4p to 140p and Investec down 13p to 497p.