on Monday will launch an "abuse of power" investigation that could be easily transformed into an even more serious process, with an expansive demand for documents from Trump's government, his family and even his real estate empire.

The President reacted to his worsening plight with a vehement defense on Sunday, after a week in which testimony from his ex-lawyer Michael Cohen deepened his political vulnerability and ahead of the expected filing soon of special counsel Robert Mueller's report.

"Presidential Harassment by 'crazed' Democrats at the highest level in the history of our Country. Likewise, the most vicious and corrupt Mainstream Media that any president has ever had to endure," Trump tweeted Sunday night.