The FTSE 100 Index has leaped 44.80 points to 5025.20 points at its close a short while ago, led by shares in Diageo.
The drinks manufacturer has advanced 24p to 811.50p, after it announced it will put to bed any further discussions with third parties to acquire assets from Allied Domecq.
Diageo has also agreed to purchase the Bushmills whiskey brand for £200m.
British Airways added 8p to 275p, after saying it will be a likely investor in radio frequency identification technology, in an aim to cut its lost-luggage bills.
Mobile phone incumbent O2 has added 3.50p to 125.75p.
On the losing side, United Utilities 'A' shares have shed as much as 166p or 33% to 340p, following yesterday's confirmation of the 165p price for new shares being issued under its rights issue plan. United Utilities shares are down about 6p to 679p.
Mining firm Xstrata, along with BHP Billiton has lost 17p to 1001p and 5.50p to 682p respectively.
In the US, the Dow Jones Industrial Average has shot up 103.31 points to 10570.34 points, led by International Paper.
The firm has added $0.62 to $33.34, along with General Motors (GM), up $0.55 to $30.97. GM has announced it will axe at least 25,000 manufacturing jobs over three years, while closing assembly plants, as a result of increasing pressure from rival firms including Toyota.
McDonalds meanwhile, has shed $0.13 to $30.28 in the morning session.IFAonline
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