"It is obvious there are some people out there who want to harm the president and that means before rushing to judgment we (must) get all the pertinent information", Efe news agency quoted Paul Ryan as saying on Wednesday.
Ryan supported the White House.
USPresident Donald Trump denied any collusion with Russian Federation in the 2016 election but said on Thursday he spoke "for myself", leaving open for the first time the possibility that some of his staff may have been involved.
FBI investigators reportedly discovered multiple contacts that are a cause for concern including Paul Manafort, former Trump Campaign Chairman, Carter Page, former Foreign Policy Advisor and Michael Flynn, the former National Security Advisor.
Collins told NPR it was too soon to tell whether the president's actions amounted to obstruction of justice.
But Rosenstein's appointment of a special prosecutor jeopardizes the chances that Comey will testify before Congress, something several committees have requested, including the House Oversight Committee, which asked Comey to appear next week.
Republicans and Democrats alike were eager to hear from Comey, who has increasingly emerged as a central figure in the unfolding drama.
During a commencement address at the US Coast Guard Academy, Trump urged graduating cadets to follow his example and "fight, fight, fight. One is, when you're put in this situation, you want to make a record, so if the other side ever tells their story, you can pretty clearly demonstrate with contemporaneous records that you acted appropriately", Miller said. Don't give in, don't back down.
Two days later, Flynn's lawyer and transition lawyers discussed the investigation of Flynn. "But it's also important that we hear direct testimony from him that would describe the context, the tone of voice the president used and the actual words that was said".
"As President I wanted to share with Russian Federation... which I have the absolute right to do, facts pertaining to terrorism and airline safety", he defensively said in two postings on his Tweet account.
On Tuesday (16 May), it was revealed that Trump asked then-FBI Director James Comey to drop the investigation into Flynn.
John McCain, chairman of the Senate Armed Services Committee, said late Tuesday that the developments had reached "Watergate size and scale".
NPR also asked Collins about her changes of position since her initial statement on the Comey firing May 9, which accepted Trump's now discarded explanation that the director had been fired for his actions in July 2016 regarding a probe of Hillary Clinton's emails and defended Trump's actions.
The White House is in a "downward spiral" and needs to do something to get "under control", Republican Senator Bob Corker has said.
The White House vigorously denied it all.
He explained that when Trump allegedly made the request to end the investigation of Flynn in February, Comey could have immediately warned the president that the conversation was inappropriate and that a request like that should never be made again.
The intensifying drama comes as Trump is set to embark Friday on his first foreign trip, which had been optimistically viewed by some aides as an opportunity to reset an administration floundering under an inexperienced president.
Flynn and other advisers to Trump's campaign were in contact with Russian officials and others with Kremlin ties in at least 18 calls and emails during the last seven months of the presidential race, Reuters reported on Thursday. Tim Scott, R-South Carolina.