A U.S. government national security panel said it identified potential risks that warrant a full investigation of Singapore-based Broadcom Ltd.¡¯s $117 billion bid for chipmaker Qualcomm Inc., a senior U.S. Treasury official said in a letter to the companies on Monday.

Shares of Qualcomm dipped 3.3 percent on growing investor concern that such government scrutiny, unusual for a deal that has not yet been agreed, would scupper any type of merger.

Some of the U.S. government¡¯s concerns relate to risks associated with Broadcom¡¯s relationships with foreign entities, Aimen Mir, the Treasury¡¯s deputy assistant secretary for investment security, said in the letter, without identifying who those parties might be.