The White House told The Independent that they haven’t confirmed the nomination and that no one is the final until they have been announced.
Ms Hartley served as the US ambassador to France and Monaco from 2014 to 2017 under President Barack Obama.
The UK ambassadorship along with the US posting to Paris are thought to be the most prestigious diplomatic positions for an American president to fill.
The London position is often considered to be the one of most consequence and heft because of the longtime diplomatic, military and historical relationship between the UK and the US.
Both the jobs in London and Paris come with historical mansions in the middle of the capitals for whoever is tapped by the president.
In the recent past, the London posting has often gone to a close friend of the president or a major donor to their campaign and has often been one of the first nominations that a new president announces.
Former President Donald Trump announced before he entered the White House that Robert “Woody” Johnson, the great-grandson of the founder of Johnson & Johnson pharmaceuticals, would serve as his UK ambassador.
The Biden administration has had problems finding the right person for the job, considering a broad arrange of possible nominees for the position, such as former New York Mayor Michael Bloomberg and former secretary of state Colin Powell, who served under President George W Bush.
The White House has also been in touch with individuals who have served as Foreign Service officers for the majority of their careers, according toThe Washington Post.
The administration reportedly considered selecting a Black person for the position. There has never been a Black ambassador to the UK from the US and the would-be historic nomination would come after Prince Harry and Meaghan Markle made allegations of racism within the Royal Household, something the family has pushed back on.
Ms Hartley was a significant fundraiser for Mr Obama and a major “bundler” for the Biden campaign. A “bundler” is someone who organizes and solicits donations from other donors. Checks from these donors can arrive in bundles, from which the expression derives.
Because of Mr Biden’s extensive list of longtime friends and supporters, some people close to the president were surprised by the Hartley pick, according to The Post.
But they also cited her support for Mr Biden from before the 2020 Democratic Iowa caucuses, where he only got the fourth-most votes. Ms Hartley didn’t give up on the Biden campaign throughout its slump, as some other donors did.
Ms Hartley has served as the chief executive at the Observatory Group, an economic and political advisory firm. She has also worked at the Department of Housing and Urban Development, as well as in the White House during the presidency of Jimmy Carter.
She’s married to the chief executive of investment bank Evercore, Ralph Schlosstein.
While the ambassador’s post has been vacant in London, career diplomat Yael Lempert has been taking up the mantle.
She’s leaving this summer to begin another State Department posting. Fellow career diplomat and Europe specialist Philip Reeker will step into the number two spot at the London embassy on 1 August.
The so-called “Special Relationship” has been considered a positive for both countries, but UK Prime Minister Boris Johnson has disparaged the term, indicating that he thought it made the UK sound “needy and weak”.
But Mr Johnson seemed to celebrate both the term and the strong links between the two countries when Mr Biden visited the UK on his first foreign trip as president last month.