The London market struggled to find direction as fears of a potential gridlock over budget measures in Washington continued to plague investors.
The FTSE 100 Index closed 15.6 points lower at 5776.1 amid fears the US election will be followed by a drawn-out battle over the looming fiscal cliff, which will mean automatic tax increases and spending cuts from January 1.
The top flight had spent much of the session ahead as upbeat economic data and progress in Greece helped overshadow concerns over the forthcoming US budget debate.
A decline in US unemployment claims and the trade deficit did not cheer investors for long as Wall Street’s Dow Jones Industrial Average also drifted into the red at the time of the London close.
Meanwhile, traders were little moved by the Bank of England’s decision to leave its quantitative easing stock unchanged at £375bn.
The mood was dampened further when Mario Draghi, head of the European Central Bank, which also left its key interest rate unchanged at 0.75%, said the outlook for the economy remains "weak".
The pound was higher against the euro at 1.25 following the no-change decision in Frankfurt, while sterling fell against the US dollar to 1.59.
The biggest Footsie risers were Randgold Resources up 120p at 7070p, Croda International ahead 29p at 2210p, British American Tobacco up 39.5p at 3174p and Burberry ahead 15p at 1214p.
The biggest Footsie fallers were Eurasian Natural Resources down 10.4p at 294.6p, G4S off 8.4p at 259.2p, CRH down 27p at 1130p and Kazakhmys off 16p at 686.5p.