William Hill is leading the FTSE 250 risers after announcing a deal to extend its reach across the US.
The bookmaker's share price rose by 3.7% to 257.65p.
Overall, the FTSE 250 is down 0.13% at 20,520.98.
Gambling operator GVC Holdings is the biggest riser on the FTSE 100. It's share price is up 1.1% at £11.08.
Paper and packaging group Mondi is the biggest faller, down 2.3% at £20.99.
The wider FTSE 100 is off 0.44% at 7,425.04.