PepsiCo Inc agreed to buy Pepsi Bottling Group Inc and PepsiAmericas Inc in a sweetened cash-and-stock deal worth $7.8 billion, the second-largest soft drink maker said on Tuesday.

PepsiCo said it will pay $36.50 per share for Pepsi Bottling and $28.50 per share for PepsiAmericas. That is up from its April bids of $29.50 per share for Pepsi Bottling and $23.27 per share for PepsiAmericas. Those bids were worth $6 billion.

PepsiCo already owned sizable stakes in the bottlers, which bottle and distribute its soft drinks. Buying the bottlers outright will result in consolidation of 80 percent of Pepsi's North American beverage volume, which Pepsi said will speed the decision-making process and eliminate friction points between the companies.

PepsiCo said both bottlers' boards of directors approved the buyout, which is expected to create annual savings of $300 million by 2012.

PepsiCo said it expects the deal to add about 15 cents per share to its earnings when the savings are fully realized in 2012.

Pepsi Bottling's shares jumped 7.2 percent to $36.05, while PepsiAmericas rose 7.4 percent to $28.10. PepsiCo shares were up 3.2 percent at $58, all in early trading on the New York Stock Exchange.

(Reporting by Jessica Hall in Philadelphia and Martinne Geller in New York; editing by John Wallace and Maureen Bavdek)