NEW YORK ( TheStreet) -- Martin Marietta Materials ( MLM - Get Report) said that it is "not dissuaded by what may be intemperate rhetoric of litigation," from Vulcan Materials ( VMC - Get Report) in its $4.6 billion hostile takeover bid for the construction materials and asphalt giant. In a letter publicly released on Saturday, Martin Marietta said that a lawsuit filed on Friday by Vulcan "serious mischaracterizes" its bid and the Vulcan board of directors are not working in shareholders best interest. "This is a remarkable statement on behalf of a Board of Directors that purportedly has not taken a public position on our proposal," Martin Marietta said in its letter. "If true, this acknowledged predetermination by the Vulcan board to refrain from engaging in meaningful discussions with Martin Marietta clearly is contrary to the best interests of Vulcan and its shareholders." On Friday, Vulcan filed a lawsuit in Superior Court of New Jersey charging that Martin Marietta had been "covertly" plotting a hostile bid and that its recent offer was an attempt to "snatch Vulcan for the lowest possible price and on its own terms," according to a Reuters report On Monday Martin Marietta made an all-stock share offer, where Vulcan will tender its shares at a ratio of 0.5 of each Martin Marietta share. The combination values Vulcan at $36.69 a share, a 15% premium to the average closing price. If a deal is struck, the combined company would dominate competitors like MDU Resources ( MDU) and Valmont Industries ( VMI) with over 4.3 billion in annual sales.