NEW YORK (REUTERS) - Shares of Campbell Soup rose on a report that activist investor Dan Loeb is planning a major shake-up at the soup and snacks maker.

The New York Post reports that Loeb sees the company as undervalued and that he is pressuring investors to explore a possible sale.

The report says his hedge fund, Third Point, is in talks with family members who control 41 per cent of the shares about backing a plan to hire a bank to consider a sale.

The Post cites sources as saying family members are interested in a sale, but its biggest shareholder, the granddaughter of founder John Dorrance, is reluctant to sell.

Campbell's shares rose on the Post report. Its shares have underperformed those of its peers, and its valuation is second lowest among them.

Investors are concerned that packaged goods companies are struggling to pass on higher costs to consumers through retailers like Walmart.

In May, CEO Denise Morrison suddenly resigned, and the company said it would review its strategic plan.