European shares closed higher on Tuesday, with merger and acquisition activity starting a shortened trading week on a positive note.
The pan-European FTSEurofirst 300 Index provisionally closed higher by 1.4 percent at 1,346.94 points on Tuesday, with many European bourses reopening after the Easter holiday period.
Novartis said on Tuesday it had agreed to acquire GSK's oncology products for $14.5 billion, plus an additional $1.5 billion contingent on a development milestone. GSK, meanwhile, will pay $7.1 billion plus royalties for Novartis' vaccines business, excluding its flu business, Novartis said.
"(It) would create the world's largest medical company, which would comfortably (be) inside the top 10 largest companies in the world with an estimated market cap of £150 billion," said Evan Lucas, market strategist at IG Markets, in a research note.
"This will be a deal to watch as it could be a major catalyst for more mega deals."
Overall, U.S. stocks rose on Tuesday, with the S&P 500 extending its longest winning run since October. Stocks advanced further after data showed existing home sales hitting 4.59 million in March, versus a 4.55 million estimate.
Back in Europe, Dutch electronics firm Philips reported a dip in net profit compared to the same period last year and shares closed around 4.7 percent lower.
Plus, a "flash" estimate from the European Commission on Tuesday indicated that euro zone consumer confidence rose to -8.7 in April from -9.3 in March.
"Hopefully, a further strengthening in consumer confidence to a 78-month high in April, stabilizing labor markets and very low consumer price inflation will increasingly underpin consumer spending and help euro zone economic recovery to gain further traction over the coming months," wrote Howard Archer, chief U.K.and European economist at IHS Global Insight.
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