HSBC helped to lift the UK market after the banking giant reported a rise in half-year profits.
Shares in HSBC rose 1.8% after it posted a 5% increase in profits to $10.2bn (£7.8bn) and announced a share buyback of up to $2bn.
The benchmark FTSE 100 index was up 21.15 points at 7,389.52 by midday.
Shares in utility companies Severn Trent and United Utilities were among the top risers after RBC lifted its rating on both firms to “outperform”.
Cigarette companies remained under pressure following Friday’s news that the US Food and Drug Administration was considering cutting the level of nicotine in cigarettes. Shares in Imperial Brands fell 5.5% and British American Tobacco dropped 4%.
On the currency markets, the pound fell 0.1% against the dollar to $1.3119 and was unchanged against the euro at 1.1182 euros.