The Footsie struggled for direction in afternoon trading as weak sales at high street bellwether Next weighed on retail stocks.
The FTSE 100 Index edged up 3.3 points to 7181.1, following several sessions in a row of top flight shares hitting all-time intraday or closing highs.
However, retailers dragged on the market after Next said the coming year would be "challenging" and that it expects to raise prices in 2017.
It added that full-price sales fell by 0.4% in the 54 days to 24 December, and adjusted annual profits to the lower end of expectations.
The fall in the value of the pound by around 16% since June 2016's Brexit vote has led the retail bellwether to reiterate previous guidance that this would feed through into price rises of up to 5% this year.
The group's forecast for full-year profits is now set at £792m ($971.4m, €931.2m) compared with previous guidance of £785m-£825m.
Marks & Spencer fell 14.5p to 330p, Burberry slipped 31p to 1469p and Associated British Foods - which owns Primark – was 89p lower at 2622p.
In afternoon trading the biggest risers in the FTSE 100 Index were Barratt Developments (+11.3p to 476.3p), Persimmon (+28p to 1788p), Taylor Wimpey (+2.4p to 158p), Vodafone (+2.9p to 205.3p) and easyJet (+12.5p to 1002p).
The biggest fallers in the FTSE 100 Index were Next (-462p to 4308p), Marks & Spencer (-14.5p to 330p), ITV (-7.9p to 200.1p), Associated British Foods (-89p to 2622p) and Burberry (-31p to 1469p).
In afternoon trading the biggest risers in the FTSE 250 Index were B&M European Value Retail (+20p to 297p), CMC Markets (+6.2p to 119.2p), Virgin Money (+13.4p to316p), McCarthy & Stone (+5.2p to164.2p), Man Group (+3.6p to 124.6p).
The biggest fallers in the FTSE 250 Index were Debenhams (-3.2p to 52p), Elementis (-10.8p to 268.6p), TP ICAP (-13.5p to 435.5p), Kaz Minerals (-10.4p to 356.8p) and Bovis Homes (-20.5p to 800p).