Aug 12 (Reuters) - Kansas City Southern said on Thursday its board determined that the unsolicited proposal received from Canadian Pacific Railway does not constitute a "superior proposal" to its agreement with Canadian National Railway Co.

CP presented a new $27 billion offer for U.S. peer Kansas City Southern on Tuesday, lower than a $29 billion rival bid from Canadian National Railway, hoping antitrust concerns over the latter will give it an edge. (Reporting by Arunima Kumar in Bengaluru; Editing by Maju Samuel)