Thailand's King Maha Vajiralongkorn has married the deputy head of his personal security, according to a royal statement.
She will now wear the title of Queen Suthida.
The surprise move came before ceremonies start on Saturday to consecrate the royal's position.
"(The King) has decided to promote General Suthida Vajiralongkorn Na Ayudhya, his royal consort, to become Queen Suthida and she will hold royal title and status as part of the royal family," the statement read.
Video from the wedding was shown on the nightly Royal News segment aired on all Thai television channels.
Members of the royal family and dignitaries, including Prayuth Chan-ocha — leader of the military government that has run Thailand since a 2014 army coup — could be seen attending the ceremony in the footage.
During the ceremony, the King poured sacred water on Queen Suthida, who also lay on the ground in front of him. The couple then signed a marriage register.
King Vajiralongkorn, 66, has been married three times and has seven children.
He became the constitutional monarch after the death of his father, the revered King Bhumibol Adulyadej, in 2016, after which a year-long period of mourning was announced.
Suthida was made a general in the Royal Thai Army in December 2016, and the deputy commander of the king's personal guard in 2017, both at the king's request.
Bhumibol Adulyadej ruled for 70 years before his death, making him the longest-reigning monarch in the world.