Silverstein's spokesperson noted surprise that the suit wasfiled as the developer believed an agreement to mediate the claimhad been reached. "It has always been our desire to avoid asenseless courtroom fight," the statement reads. "Daniel Libeskindhas already been paid many millions of dollars for his work by theLMDC and the Port Authority and is unable to provide any industrystandard timesheets or other documentation that would justify anadditional payment of more than $800,000."

Last July, an "historic collaboration" was announced betweenSkidmore Owings & Merrill, a firm handpicked by Silverstein,and Studio Daniel Libeskind to design the world's tallest buildingat the World Trade Center site. Libeskind is suing for fundsassociated with that collaborative effort. Libeskind had beendesignated by the Port Authority of New York and New Jersey as themaster plan architect for the site, beating out seven otherarchitectural teams.