Senators have issued stern warnings to Donald Trump not to fire his attorney general or the special counsel investigating Russian interference in the US election.
Republican Lindsey Graham said Attorney General Jeff Sessions and Special Counsel Robert Mueller should keep their positions.
“If Jeff Sessions is fired there will be holy hell to pay,” Mr Graham said.
He added: “Any effort to go after Mueller could be the beginning of the end of the Trump presidency – unless Mueller did something wrong.
“Right now I have no reason to believe that Mueller is compromised”.
“Some of the suggestions the President is making go way beyond what’s acceptable in a rule of law nation,” said Mr Graham.
The senator is one of three preparing a bill to shield Mr Mueller from being sacked.
The others working on the effort are Sheldon Whitehouse and Richard Blumenthal, both Democrats. All three are on the Senate Judiciary Committee.
It is unclear when the bill would be introduced.
Mr Blumenthal said that the bill “might be a committee effort” and said it would protect Mr Mueller and other special counsels.
He said firing Mr Mueller “would precipitate a firestorm that would be unprecedented in proportions”.
Many Republicans have expressed strong support for former Mr Mueller, a former FBI director who was appointed to investigate allegations of Russian meddling in the US election and possible links to the Trump campaign.
They have also rallied around Mr Sessions, who has recently become a daily target of critical tweets from Mr Trump.
He has publicly scorned Mr Sessions for recusing himself from the investigation into election meddling after he admitted to meeting Russia’s ambassador during the campaign.
The President said he rued his decision to select him.
His criticism has fuelled speculation that Mr Sessions may step down – even if the President stops short of firing him.
But he is showing no outward signs that he is planning to quit, and White House press secretary Sarah Huckabee Sanders has said Mr Trump “wants him to lead the department”.