The FTSE 100 fell slightly on Wednesday after being weighed down by banks and commodities stocks.
The blue-chip index fell 1.61 points, or 0.02%, to end the day at 8343.85.
Banking stocks also dipped, with NatWest, Barclays, Lloyds and HSBC all falling on fears that the Government might impose heavier taxes on the sector.
Prime Minister Sir Keir Starmer warned of a “painful” Budget in October earlier this week.
Sir Keir argued “those with the broadest shoulders should bear the heavier burden” during a speech from Downing Street’s rose garden on Tuesday.
Dan Coatsworth, investment analyst at AJ Bell, said: “It’s about as easy a target as you can get. No-one is going to shed any tears if the banks are forced to hand over more of their profits.
“Banks have made big money from higher interest rates, profiting when the rest of the country has struggled through a cost-of-living crisis.
“If the oil and gas industry can be slapped with a windfall tax as a result of a spike in energy prices, so can the banks as a result of higher rates.”
Mr Coatsworth added: “Investors didn’t like their chances and were quick to sell down shares in NatWest, Barclays, Lloyds and HSBC.”
At the end of the day in Europe, Frankfurt’s Dax index rose 0.57% while the Cac 40 in Paris closed up 0.16%.
In New York a little while after markets had closed in Europe, the S&P 500 was trading down 0.56% while the Dow Jones was 0.31% lower.
On currency markets, the pound was trading 0.46% lower against the dollar at 1.32 and had risen 0.06% against the euro at 1.1864.
Meanwhile, mining stocks were also down. Antofagasta fell significantly amid a dip in copper prices, with its share price dropping 5.97% for the day.
Endeavour Mining and Fresnillo also slumped after a drop in gold prices, with the miners down 2.87% and 1.44% respectively.
Brent crude oil futures were down 0.74% to 78.96 US dollars as markets were closing in London.
The biggest risers on the FTSE 100 were CocaCola HBC, up 84p to 2826p, BAE Systems, up 28p to 1348p, GSK, up 33.5p to 1651.5p, United Utilities, up 17.9p to 1015.5p, and Aviva, up 7.2p to 505.2p.
The biggest fallers on the FTSE 100 were Antofagasta, down 114p to 1796.5p, JD Sports, down 5.8p to 137.3p, Natwest Group, down 11.4p to 338p, Endeavour Mining, down 47p to 1591p, and Barclays, down 6.3p to 223.9p.