According to the report, First Lady Melania Trump, originally from Slovenia, is said to have been personally involved in the selection of Roberts.

A source familiar with the selection process told the magazine Melania Trump was presented with dossiers of several potential candidates and endorsed Roberts, mainly because she felt that the US would be best represented by a member of the business community.

Kelly Roberts and her husband Duane Roberts have contributed over $1.2m to Republican candidates and committees in the past year. Kelly herself donated $50,000 to Trump's campaign in October 2016.

The magazine says that it is not uncommon for donors to be appointed as US ambassadors to countries that are not seen as hot spots, but that of the eight US ambassadors to Slovenia so far only one was not a career diplomat - businessman Yousif Ghafari, who served in Slovenia between May 2008 and January 2009.

According to the report, Kelly Roberts serves as vice-chair and chief operating officer of the Mission Inn Hotel and Spa in Riverside, California. She is said to take an active role in the day-to-day management of the historic property, which she and her husband have owned since 1992.

Roberts has strong support from Republicans in California's congressional delegation, with House Majority Leader Kevin McCarthy taking the lead on advocating for her appointment, New York Magazine reported.

Brent Hartley, who currently serves as US ambassador to Slovenia, is a career diplomat who was previously the No. 3 at the Bureau of European and Eurasian Affairs of the State Department. He has been in office in Ljubljana since February 2015.