Trump is accused of appointing Acting Attorney-General Matthew Whitaker to kill off the Russia investigation, with Whitaker known to oppose the probe. Democrats have filed a series of lawsuits seeking to overturn the appointment.
The party now plans to use its majority in the House of Representative to further investigate the President's financial ties to determine whether they are the "hidden hand" driving US foreign policy on Russia and Saudi Arabia, the incoming chairman of the House Intelligence Committee said.
Adam Schiff, the ranking Democrat on the committee, accused Trump of being "dishonest" about the role of Saudi Crown Prince Mohammed bin Salman in the murder of journalist Jamal Khashoggi.
Trump claimed the CIA had not reached a conclusion on the royal's involvement, as he refused to condemned the Crown Prince or cut ties with the Saudis, releasing an extraordinary statement in support of the country.
Schiff, who was briefed on the CIA report, said the panel will look into the Trump family's business ties with Saudi Arabia and whether "personal financial interests" drive US-Middle East policy.
The California Congressman said Trump was signalling to despots he will have "their back" if they praise or do business with him.
CNN security analyst Peter Bergen said the President was perfecting "the art of the giveaway" with overseas dictators, missing another massive opportunity for the US.
"Other presidents would have taken advantage of this international outrage to get some American wins on the board," he writes.
He cited ending the Saudi-led war in Yemen, lifting the Saudi-led blockade of Qatar, releasing jailed Saudi civil society activists who face execution, and obtaining Saudi funding for the reconstruction of Iraq and Afghanistan.
