BANGKOK — Thai Union Frozen Products announced Friday it is acquiring Bumble Bee Seafoods, a major seller of canned tuna in the United States, for $1.5 billion.

The Thai company, known as TUF, said the purchase of Bumble Bee, which is owned by private equity firm Lion Capital, is expected to be completed by the second half of 2015, pending approval by U.S. antitrust authorities.

Thai Union's statement says it has annual sales exceeding 100 billion baht ($3 billion) with a worldwide workforce of more than 35,000. San Diego-based Bumble Bee generates annual sales of approximately $1 billion with a workforce of more than 1,300 people.

The Thai company already owns Chicken of the Sea, another major U.S. provider of packaged seafood.

Thiraphong Chansiri, the president and CEO of Thai Union, said the purchase was the company's largest acquisition ever.

"Upon completion, the transaction will be immediately accretive to TUF's earnings and cash flows," he said. Absorbing Bumble Bee would lower costs and improve efficiency.

Other international brands controlled by Thai Union include John West, King Oscar, Petit Navire, Parmentier, Mareblu, and Century.