US stocks opened higher today, extending gains from a big rally last Friday, as a flurry of merger developments in the US and overseas lifted sentiment. The Dow Jones rose 35 points to 10,438 and the Nasdaq added nine points to 2,099 in the first trades.

The merger news includes a $39.2 billion bid from Canada's Barrick Gold for Placer Dome, and Spanish company Telefonica's offer of almost £18 billion sterling for British mobile phone operator O2. Swiss pharmaceuticals group Novartis also said it had reached a deal to buy US biotechnology firm Chiron, one of the world's largest producers of influenza vaccines for $5.1 billion.

European stock exchanges jumped today as investors seized on news of that friendly cash bid by Telefonica for O2. London's FTSE surged 86 points to stand at 5,299 just before 3pm, with shares in O2 soaring. Other telecom stocks were also higher on news of the deal with Vodafone up almost 2.5% and its former owner BT Group up almost 2%. Meanwhile the Paris CAC jumped 82 points to 4,408 and the Frankfurt DAX gained 79 to stand at 4,905.

Dublin's ISEQ index was also stronger this afternoon, up 102 points to stand at 6,567 just before 3pm - a gain of 1.5%. Shares in the banks were stronger with AIB jumping 50 cent to €17.50 and Anglo Irish Bank gaining 25 to €11.25. Shares in Eircom were up 10 to €2.