LONDON (The Deal) -- Drink can maker Rexam has agreed to a takeover offer from Broomfield, Colo.-based peer Ball (BLL - Get Report) that values the London group at about £5.4 billion or $8.3 billion including debt, the companies said Thursday.

Ball will offer the same two-thirds, one-third mix of cash and stock flagged two weeks ago, but the value of the offer has risen to 628 pence per Rexam share from 610 pence share, based on Ball's Tuesday closing price and exchange rates on that day. Based on that price, Ball will pay £4.4 billion for Rexam's equity, up from the expected £4.3 billion.

The agreement came as Rexam warned of "headwinds" this year including higher metal prices in its full-year results.

Ball said that it will derive $300 million of synergies from the takeover by 2018 and that the transaction will be "highly accretive" to earnings, lifting profit from the first full year. But the companies don't expect to obtain all the regulatory clearances that they need for the fusion until the first half of next year, reflecting what will likely be tough antitrust reviews of the transaction in various jurisdictions.

"The combination of Ball and Rexam creates a global metal beverage packaging supplier capable of leveraging its geographic presence, innovative products and talented employees to better serve customers of all sizes across the globe, while at the same time generating significant shareholder value," Ball President, Chairman and Chief Executive John A. Hayes said in a statement.

If it proceeds as planned, Rexam shareholders will end up with 19% of the enlarged U.S. company and will receive a premium of 40% to Rexam's undisturbed price as of Feb. 4, based on the price of 628 pence a share.

The agreement comes after a period of retrenchment at Rexam. Last year, it sold off its health care-packaging businesses in two separate transactions worth a combined $940 million.

In 2012, it shed its personal-care business to Boca Raton, Fla.-based Sun Capital Partners, which paid $459 million, and Stamford, Conn.-based Silgan Holdings (SLGN - Get Report) , which paid $250 million.

Rexam on Thursday said that full-year revenue declined 3% to £3.83 billion, though it rose 2% on an "organic" basis, while underlying pretax profit declined 3% to £360 million.

Chief Executive Graham Chipchase warned of a "tough trading environment with headwinds from metal premium, foreign-exchange volatility and pricing pressure" this year.

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Two weeks ago, Ball reported that 2014 net profit had risen to $552.8 million, from $489.6 million.

As well as drink cans, Ball also makes cans for products including food, paints, candy and lip balm as well as aerosols. Ball's other business line is aerospace components.

Its group revenue last year was $8.57 billion, up from $8.47 billion a year earlier.

Ball had a market value of almost $10.6 billion as of Wednesday's close, up from $9.1 billion just before the disclosure of the Rexam talks two weeks ago.

Ball has operations in the Americas, Asia Pacific and Europe, while Rexam operates in the Americas, Europe, and the Middle East. Antitrust trouble spots could include Europe, where the combination is estimated to have more than two-thirds of the drink can market in Brazil and North America.

It will acquire Rexam though a scheme of arrangement, which requires clearance from both sets of shareholders. The cash/stock split is 407 pence in cash 0.04568 of a Ball share per Rexam share.

The long stop date for the agreement is Aug. 19, 2016.

Rexam shares were up 4.2%, or 22.5 pence, at 559.50 pence in London on Thursday morning.

Ball's financial advisers are Deutsche Bank's Niall Cullinane and Richard Sheppard; Goldman Sachs' Peter Brundage, Peter Guidotti and Nimesh Khiroya; and Greenhill's Pieter-Jan Bouten, Douglas Jackson, Glenn Tilles and David Wyles.

A Skadden Arps Slate Meagher & Flom team including Helena Derbyshire, Shilpi Gupta, Michael Hatchard, Hal Hicks, Scott Hopkins, Seth Jacobson, Lynn McGovern, Charles Mulaney Jr., Tim Sanders, Clive Wells and Joseph Yaffe is acting as lead legal adviser, and Axinn Veltrop & Harkrider is acting as lead antitrust adviser.

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Bank of America Merrill Lynch, Deutsche Bank Securities, Goldman Sachs Bank USA, KeyBank National Association, Rabobank and Royal Bank of Scotland Group are providing debt financing to Ball, which will also use cash on hand to pay for Rexam.

Rexam's advisers are Bank of America Merrill Lynch's Jonathan Bewes and Peter Luck; Barclays' Asim Mullick, Andrew Owens and Richard Taylor; Credit Suisse Group's Lewis Burnett and Stuart Field; and Rothschild's Ravi Gupta, Nick Ivey and Yuri Shakhmin.

Freshfields Bruckhaus Deringer's Doug Bacon, John Davies, Thomas Ensign, Colin Hargreaves, Kathleen Healy, Julian Long, Martin McElwee, Sarah Murphy, Mitchell Presser, David Sonter and Paul Yde are Rexam's legal advisers.

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