The White House is discussing plans to replace Secretary of State Rex Tillerson with CIA chief Mike Pompeo, US media say.
Tillerson has been at odds with Trump over foreign policy recently.
The secretary of state was even reported to have privately described the president as a "moron".
They have differed in their approach to North Korea's missile testing and Iran's nuclear programme, among other issues.
Two White House officials were quoted by Associated Press as saying a plan was being discussed, and unnamed government sources also spoke to the New York Times and Vanity Fair.
Pompeo would be replaced at the CIA by Republican Senator Tom Cotton, the New York Times reports.
However, it is not yet clear whether Trump has given final approval to the move, the NYT reports.
Failure to navigate Washington politics
Tensions between Trump and Tillerson have been widely reported. That seems partly for personal reasons - the two are chalk and cheese in temperament and the way they work. But Trump is also said to have complained that his secretary of state is too "establishment".
The president has undermined Tillerson on key policy areas with his fiery tweets. Yet he's also quietly accepted the secretary's diplomatic strategy on issues like North Korea, suggesting the relationship is more complex than reported.
Separately, Tillerson's management style has also alienated chunks of his natural constituency: many in the state department, Congress, and foreign policy community. That's because he accepted Trump's proposed budget cuts without much of a fight and, at the same time, launched a major redesign of the department without saying where it was heading or explaining the details.
There's also been an exodus of dismissed or disillusioned senior staff who aren't being replaced quickly enough. Not all of this is Tillerson's fault, but he has failed to navigate the push and pull of Washington's politics.
What has the official reaction been?
The White House has said Tillerson remains in post.
"As the president just said: 'Rex is here,'" White House spokeswoman Sarah Sanders said in a statement.
"There are no personnel announcements at this time.
"Secretary Tillerson continues to lead the state department and the entire cabinet is focused on completing this incredibly successful first year of President Trump's administration."
In further reaction to the reports, Senate Foreign Relations Committee Chairman Bob Corker said Tillerson was "unaware of anything changing".
Why would Trump want Tillerson gone?
They don't appear to get on.
Trump's disenchantment with Tillerson, a former chief executive of energy giant Exxon Mobil, has been rumoured for some time.
The secretary of state has defended the multi-party deal to curb Iran's nuclear ambitions in return for a loosening of sanctions - an agreement derided by Trump.
The president also said in October that Tillerson was "wasting his time" trying to bring about diplomatic contacts with North Korea as it continues to build up its missile and nuclear capabilities.
Twitter post by @realDonaldTrump: I told Rex Tillerson, our wonderful Secretary of State, that he is wasting his time trying to negotiate with Little Rocket Man...
The "moron" comment is unlikely to have helped relations either.
And in June, Trump and Tillerson were giving out contradictory messages about the dispute between Saudia Arabia and Qatar.
The secretary of state warned that the Saudi-led blockade of Qatar could affect the fight against extremism and was having humanitarian consequences.
Trump, on the other hand, appeared to endorse Saudi policy, suggesting the blockade might herald "the beginning of the end to the horror of terrorism" - a reference to allegations Qatar allows funding of extremist groups.
To add to Tillerson's woes, his plans for radical restructuring of the state department are not going down well in some quarters.
His announcement that he would "create the state department of the future" involves sacking career diplomats, and budget cuts.
Democrats, and some Republicans, have expressed concern the restructuring could undermine America's interests abroad.
What are the possible wider changes?
The secretary of state's firing would form part of a wider national security team shake-up overseen by White House Chief of Staff John Kelly, the NYT reports.
Pompeo, as Tillerson's possible replacement, is reputed to be closer to Trump on security issues.
And Tom Cotton, the Arkansas senator and reported choice for new CIA head, holds similar views to the president on the Iran nuclear deal.
The decorated Iraq and Afghanistan war veteran is described as a hawk who wants to increase the defence budget.
Tillerson, 65, was appointed in January and his sacking would cap one of the shortest tenures for an American secretary of state.
His appointment was a controversial one, thanks to his close links to Russian President Vladimir Putin stemming from his work on major oil contracts in Russia.
The Trump administration faces several investigations into whether there was collusion between his election campaign and Russian officials.
Tillerson was on the verge of retirement when he was asked to fill the role.
Interviewed earlier this year by the conservative website, Independent Journal Review (IJR), he was quoted as saying: "I didn't want this job. I didn't seek this job... my wife told me I'm supposed to do this."