Easyjet was the biggest riser on the index, with traders citing reports that it could be a target for US leasing company AerCap.
The FTSE 100 was down 15.73 points at 6,853.23, with little company news about to move the market.
In the FTSE 250, William Hill shares rose 5% after it raised its full-year profit outlook.
The bookmaker said 2016's operating profits would be at the higher end of its previous guidance of £260m-£280m.
Its comments, issued late on Thursday, came shortly after Rank and 888 abandoned their attempt to merge with the bookmaker in a complex three-way tie-up.
The two companies said they had not been able to "meaningfully engage" with William Hill's board.
On the currency markets, the pound fell 0.36% against the dollar to $1.3120 and dropped 0.1% against the euro to €1.1588.
(Noon): The FTSE 100 fell, but shares in Easyjet rose 2% on speculation that the airline could be a takeover target.