American Can said it will acquire two firms.

Under terms of the proposals, Greenwich, Conn.-based American Can will acquire Berg Enterprises of Iselin, N.J., for about $125 million and Financial Institution Services of Nashville, Tenn., for about $45 million. Completion of both acquisitions is subject to definitive merger agreements, American Can said. The transactions are expected to be completed by July. Berg is engaged principally in mortgage banking and has interests in residential and commercial real estate syndication and management. Financial Institution Services is a developer and marketer of programs used by banks and S&Ls; to attract and retain depositors.