The London market struggled for direction amid a slump in Unilever shares after US food rival Kraft abandoned its $143bn (£115bn) takeover at the weekend.
Kraft, which owns Heinz baked beans and Philadelphia cream cheese, said it had "amicably agreed" to withdraw its proposal, in a joint statement from the pair on Sunday. Less than 48 hours after the bid was announced.
This comes after Unilever, makers of Dove soap and Marmite, rejected the bid on Friday afternoon as undervaluing the business.
The FTSE 100 Index edged up 0.9 points to 7300.8, as Anglo-Dutch Unilever fell 7%, or 262p to 3535p, once traders recognised all hopes of a deal were over.
CMC Markets chief market analyst Michael Hewson said: "There had been widespread speculation that this bid may well have turned out to be a rather protracted affair given some of the politics involved. Kraft's quick about turn appears to have drawn a line under that, over concerns that any public battle could have the potential to turn increasingly bitter."
The biggest afternoon risers in the FTSE 100 Index were Royal Bank of Scotland (+15.2p to 257.6p), Rolls-Royce (+27p to 693p), Direct Line Insurance (+10.6p to 364.5p), Hammerson (+14p to 578.5p) and Merlin Entertainments (+10.2p to 500p).
The biggest afternoon fallers in the FTSE 100 Index were Unilever (+262p to 3535p), Pearson (-27p to 641.5p), Mediclinic International (-20p to 808p), Coca-Cola HBC (-32p to 1957p) and Imperial Brands (-53p to 3728p).
The biggest afternoon risers in the FTSE 250 Index were Tullow Oil (+8.5p to 267.8p), SIG (+2.6p to 111.1p), OneSavings Bank (+7.8p to 395p), Nostrum Oil & Gas (+9p to 469p) and Inmarsat (+12p to 627p).
The biggest afternoon fallers in the FTSE 250 Index were Bovis Homes (-83p to 758p), BGEO Group (-166p to 2940p), Petra Diamonds (-5.5p to 143p), Essentra (-12p to 472.5p) and PZ Cussons (-7.1p to 315p).