U.S. lawmaker threatens to subpoena White House over Ukraine documents

  The chairman of a congressional panel helping to spearhead an impeachment inquiry into President Donald Trump said on Wednesday he plans to issue a subpoena to the White House for documents relating to the administration's contacts with Ukraine.

"The White House's flagrant disregard of multiple voluntary requests for documents — combined with stark and urgent warnings from the Inspector General about the gravity of these allegations — have left us with no choice but to issue this subpoena," House Oversight Chairman Elijah Cummings wrote in a memorandum to committee members.