Former national security adviser wrote that US president wanted to withhold military aid from Ukraine until it helped with an investigations into his Democratic rival

New York Times says former national security adviser's description of exchange with Trump appears in drafts of his forthcoming book submitted to White House ahead of publication

As final preparations made for Senate trial, president's legal team claims process is 'dangerous perversion of Constitution,' worthy of condemnation

Giuliani associate says president was fully aware of efforts to pressure Ukraine to investigate Joe Biden, he 'knew exactly what was going on'

Government Accountability Office says 'the President is not vested with the power to ignore or amend' funding approved by Congress

US State Department won't comment on Kyiv's investigation into alleged illegal activity targeting Marie Yovanovitch

Lev Parnas says he delivered messages to Zelensky about opening Biden probe on direct orders from Trump's lawyer, and US president 'knew exactly what was going on'

Lev Parnas and Igor Fruman tried to appoint amenable CEO for gas company, boasted they were going to get Trump administration to fire envoy known for fighting corruption

Democratic leaders expected to announce formal charges of abuse of power and obstruction of Congress as soon as Tuesday; proceedings likely to only focus on Ukraine

Trump distances himself from Giuliani, saying he had not asked him to go to Ukraine on his behalf and did not know what he was up to