President-elect Trump has nominated Kimberly Guilfoyle, the former Fox News host who was once engaged to Donald Jr., to be the US ambassador to Greece in the new administration.

“Kimberly Guilfoyle has been a close friend and ally for many years. Her experience and leadership in law, communications, and politics, along with her sharp intellect, make her uniquely qualified to represent and protect American interests abroad,” US President-elect Donald Trump posted on the social network Truth Social on December 10.

Mr Trump announced that Guilfoyle, 55, a lawyer and former Fox News host, would become US ambassador to Greece.

The US President-elect is confident that Guilfoyle is perfectly suited to promote bilateral relations with Greece, promoting US interests on issues ranging from defense cooperation to trade and economics.

Attorney Kimberly Guilfoyle speaks at the Republican National Convention in Milwaukee on July 17. Photo: AP

Guilfoyle is a staunch Trump ally who spoke at the Republican National Convention in July. She was previously engaged to Donald Jr., 46, but recently split, according to US media.

Ahead of his inauguration on January 20 next year, Mr. Trump is gradually completing his administration, most of whom are close to his family or loyal to him.

The president-elect previously selected real estate developer Charles Kushner, father of son-in-law Jared Kushner, as US ambassador to France. He also selected businessman Massad Boulos, father-in-law of daughter Tiffany Trump, as senior adviser on Arab and Middle East affairs.