The world's two largest beverage can makers by volume want to merge to better manage capital spending and cut costs. The European Commission however fears the deal would push up prices for companies and consumers.

The combined company would have 60 percent of the beverage can market in North America, 69 percent in Europe and 74 percent in Brazil, according to Morningstar analysts.

Ball is prepared to divest four factories in Germany, three in the UK, one each in Spain, France, the Netherlands and Austria, the sources said. Nine of the plants make cans and two of them can ends. The offer was submitted to the Commission last week.

The EU competition authority has given third parties until Wednesday to provide feedback and is likely to extend the deadline. It is scheduled to decide on the case by Jan. 22.

Ball has said it is willing to sell more than $1.58 billion worth of assets to allay regulatory concerns.

Rexam's customers include Coca-Cola Co and Anheuser-Busch InBev.

By Foo Yun Chee