WASHINGTON • It is among the most persistent parlour games in Washington: Secretary of State Rex Tillerson is said to be ready to bolt - or be fired - at any moment.
And Ms Nikki Haley, the US envoy to the United Nations, may already be angling to take his slot.
During a week in New York for the UN General Assembly, Mr Tillerson said he has no intention of leaving his job and Ms Haley said she does not covet it. But their busy, mostly separate, schedules produced fresh speculation about their intentions.
It also underscored the far different styles of Ms Haley, the ebullient former South Carolina governor, and Mr Tillerson, the low-key former oil company chief executive.
"Haley certainly had a satisfying week, and she is now becoming one of the President's main proxies" on both North Korea and Iran, said Mr Richard Gowan, a UN expert with the European Council on Foreign Relations.
"Tillerson made relatively little impact at the UN, but nor did he make any major gaffes. He was in diplomatic-workhorse mode."
Ms Haley is a practised communicator who maintains an active Twitter feed where she mixes stern messages to North Korea with pictures of her alongside President Donald Trump and occasional love notes to her husband.
PEOPLE ARE ALWAYS GOING TO TALK
There's going to be chatter about things. Ever since I was a legislator, people have talked about what I'm trying to do or what I'm supposed to do. What I'm trying to do is, do a good job.
MS NIKKI HALEY, the US envoy to the United Nations, on whether she was angling to replace Secretary of State Rex Tillerson.
Mr Tillerson is intensely private, with a wit so dry his humour is sometimes hard to discern.
His aides have scoffed at reports that Mr Trump has lost confidence in him and note that the Secretary of State was in on most of Mr Trump's meetings with world leaders in New York. But Ms Haley had a higher public profile, sitting next to the President in his first appearance at a session promoting goals to reform the UN.
Ms Haley considers herself a peer of Mr Tillerson, not an underling, despite his higher rank in the Cabinet and his status as the top US diplomat.
That was underscored earlier this month when she delivered a speech to the American Enterprise Institute laying out strategies for tackling Iran's nuclear programme.
The US mission to the United Nations did not coordinate the speech with the State Department, and officials at the department were left bewildered because it did not represent the official State Department position, according to people familiar with the event who asked not to be identified describing the lack of communications.
Ms Haley's spokesman said she had cleared it with the White House and through the National Security Council's inter-agency process.
She kept her own schedule, unlike some of her predecessors as UN ambassador who spent most of General Assembly week shepherding the Secretary of State to meetings.
Last Thursday evening, she held forth alone before reporters in a news conference boasting of the Trump administration's successes at the UN while Mr Tillerson was tied down in a Security Council debate about non-proliferation.
She went ahead despite a State Department note advising her to wait until Mr Tillerson had finished. She shrugged off a reporter's question about whether she was angling to replace Mr Tillerson with people-will-talk nonchalance.
"There's going to be chatter about things," she said. "Ever since I was a legislator, people have talked about what I'm trying to do or what I'm supposed to do. What I'm trying to do is, do a good job."
Pressed again about whether she wants Mr Tillerson's job, she said: "No, I do not."
Mr Tillerson, who seldom makes TV appearances, had the last word, at least for now.
"I think we have a Secretary of State currently, and I think he's planning to hang around," he said when he appeared last Friday morning on ABC's Good Morning America.