The FTSE 100 closed up 0.02% on the day as a slight rise in the pound put pressure on companies that sell a lot of their products in dollars.
By the end of the day, the index had gained only 1.36 points, ending at 7,466.6, its highest close since early September.
Things were happier elsewhere in Europe, with Germany’s DAX up 0.8%, while Paris’ CAC 40 rose 0.4%.
“European markets enjoyed a relatively positive day, as Thanksgiving celebrations led to lower volumes and volatility,” said Joshua Mahoney, senior market analyst at online trading platform IG.
“The German Ifo Business Climate Survey released in the morning created grounds for optimism just a day after the release of PMI surveys eased fears of a severe recession in the region.”
He said the survey showed that traders were more positive about the future, though pessimistic about the present.
In energy markets, the price of Brent crude remained more or less unchanged, down just 0.4%, at $85.06.
In the currency markets, the pound rose by about 0.6%, to reach $1.21. Against the euro, it rose 0.5%, to 1.16.
In company news, shares of fashion brand Dr Martens plunged after the shoemaker gave investors a warning about its profit margins for the entire fiscal year.
It said consumer demand weakened as its sales were slower than expected during the fourth quarter.
Shares of Dr. Martens fell 22.7%.
In better news, vacation company Jet2 told investors it turned to a first-half profit as demand for summer vacations increased after pandemic restrictions were lifted.
It said its full-year earnings would be better than expected even though the group is facing significant cost pressures such as fuel and staff wages.
Jet2 shares rose 2.9%.
B&Q owner Kingfisher said its revenue has been boosted as more people seek to improve the energy efficiency of their homes, with roll top insulation sales doubling.
The DIY giant told investors it was managing cost inflation effectively, but that its earnings could be lower than previously expected.
However, Kingfisher slid toward the bottom of the FTSE 100 as its shares fell 1.6%.
The biggest gainers on the FTSE 100 were Intertek Group, up 176 points to 4,036p, United Utilities Group, up 34p to 1,086p, Rolls-Royce Holdings, up 2.64p to 91.05p, and Airtel Africa, up 3.3p to 91.05p. 120.6 pixels wide, and Segro, up 21.1 pixels to 837.2 pixels.
The biggest losers in the FTSE 100 were Imperial Brands, down 85p to 2100p, British Land, down 9p to 406p, Vodafone, down 1.99p to 92.67p, London Stock Exchange Group, down 152p to 8.080p, RS Group, down 17.5p to 8.080p. 958p.