Relief that TUI weathered this summer's heatwave (see post at 8:49am) sent shares in the travel company to the top of the FTSE 100 this morning, up 1.95% at £14.64.
Distribution group DCC saw its shares lead the biggest losers, down 4.1% at £70.12, after it said it would buy musical instruments specialist Jam Group for $170m (£130m).
It plans to issue new stock to finance acquisitions.
The FTSE 100 is down 5.81 points at 7,505.68.
IG Group's shares tumbled by 8.7% to 669.5p - the biggest faller on the FTSE 250 - after it announced that its chief executive was stepping down with immediate effect.
TalkTalk topped the gainers, up 3.1% at 125.25p.
The FTSE 250 is down 0.36% at 20,362.22.