Sharecast - At 0830 BST, the FTSE 100 was down 0.2% at 7,819.10.
Shares in NatWest (LON:NWG) fell despite the UK bank reporting better-than-expected first-quarter profit driven by higher interest rates, as it also posted a sharp drop in deposits as customers chased better rates, with incomes squeezed by rising inflation. Lloyds (LON:LLOY) was also in the red.
Matt Britzman, equity analyst at Hargreaves Lansdown, said the outflow of customer deposits over the quarter was "not cause for concern", however.
"Consumers shopping around for the best rates isn't much of a surprise, given they've spent years getting little to nothing from their cash deposits," he said. "For now, higher interest rates are doing their job to prop up earnings and offset the impact of a more challenging and competitive mortgage market."
Miners were among the worst performers on the top-flight index, with Antofagasta (LON:ANTO), Glencore (LON:GLEN), Anglo American (LON:AAL), and Rio Tinto (LON:RIO) all down.
Renishaw (LON:RSW) was under the cosh after it downgraded its full-year profits and revenue guidance amid lower demand from the semiconductor and electronics sectors.
On the upside, Asia-focused insurer Prudential (LON:PRU) was the top gainer on the FTSE 100 as it reported a jump in first-quarter sales and new business profit.
Pearson (LON:PSON) was also a high riser as the education publisher said it was on track to meet annual guidance and announced a £300m share buyback to start in the second half of the year, as it posted a 2% jump in total group sales in the first quarter.
Corrugated packaging company Smurfit Kappa (LON:SKG) was up after it reported a rise in first-quarter profit despite a dip in sales.
Hikma (LON:HIK) gained as it upgraded full-year guidance after a stronger-than-expected start to the year for its generics business, but expressed concern about the impact of the current conflict in Sudan on operations.
Specialist engineer Rotork (LON:ROR) advanced after saying it expects 2023 adjusted operating profit to be slightly ahead of expectations driven by strong order intake.
Outside the FTSE 350, broker Numis (LON:NUM) surged more than 60% after agreeing to be bought by Deutsche Bank (ETR:DBKGn) in a £410m cash deal. Under the terms of the transaction, DB will pay 350p per share.