BBC report says, Vice-President Mike Pence has hired an outside lawyer to handle his response to inquiries into possible ties between President Trump's campaign and Russia.
Richard Cullen is known for representing high profile clients.
Earlier, report says, Mr Donald Trump was being investigated by special counsel Robert Mueller for possible obstruction of justice.
Mr Mueller is leading an FBI inquiry into Russia's alleged interfering in the 2016 presidential election.
Also, another report says, senior intelligence officials would be interviewed on whether Mr Trump tried to end an inquiry into his sacked National Security Adviser Michael Flynn, and about the firing of FBI chief James Comey.
Mr Trump denied any connection with Russia.
He said: "You are witnessing the single greatest WITCH HUNT in American political history."