again from our nbc news headquarters here in new york. day 679 of this trump administration. the day the president was hit with a legal bombshell as robert mueller secures a guilty plea from the man who was once one of trump's most loyal lieutenants. today michael cohen, the president's former personal lawyer, admitted to lying to congress about his boss's involvement in a project to build a moscow version of trump tower as he was securing the republican nomination back in 2016. and perhaps worse than that, cohen admits to being in touch with the kremlin during a presidential campaign. cohen's plea came this morning in federal court in new york as part of a cooperation deal with mueller. in court documents, cohen explained his motivation. quote, i was aware of donald trump's repeated disavowals of commercial and political ties between himself and russia, and that any contact with russian nationals by the trump campaign or the trump organization had all terminated before the iowa caucus in february of 2016.