(Reuters) - Rexam Plc (>> Rexam PLC), the world's No. 2 drinks can maker by revenue, posted a better-than-expected underlying pretax profit for the first half as increased volumes softened the effect of high aluminium prices and a stronger pound.

The company's shares rose as much as 3.7 percent, making the stock the second-biggest gainer on the FTSE-100 Index <.FTSE>.

Rexam reported a 4 percent rise in beverage can volumes, driven mostly by strong organic growth in Europe.

Aluminium premiums, or the cost to get metal out of storage, have soared to all-time highs in Europe and North America.

The surge in premiums pushed up the company's net additional costs to 7 million pounds in the first half.

Rexam competes with U.S.-listed Ball Corp (>> Ball Corporation) and Crown Holdings (>> Crown Holdings, Inc.), and is the only beverage can maker listed on the London Stock Exchange.

Rexam's underlying pretax profit fell to 166 million pounds for the six months ended June 30 from 169 million pounds a year earlier, beating the average analyst estimate of 156.6 million pounds.

Revenue fell 5 percent to 1.88 billion pounds, but was higher than analysts' average expectation of 1.85 billion pounds.

Shares in the company were up 0.3 percent at 502.5 pence at 11:33 BST on the London Stock Exchange.

(Reporting by Aashika Jain in Bangalore; Editing by Robin Paxton and Simon Jennings)

Stocks treated in this article : Ball Corporation, Crown Holdings, Inc., Rexam PLC