King Maha Vajiralongkorn of Thailand has unexpectedly wed the deputy chief of his own security detail in a ceremony three days before his official coronation.

Vajiralongkorn's new wife has been given the title Queen Suthida after an announcement about the nuptials was placed in the royal gazette, followed by video footage of the wedding being shown on television news in Thailand.

Vajiralongkorn inherited the role of constitutional monarch following the death of his father King Bhumibol Adulyadej in 2016 and was due to be official crowned king over the weekend in Buddhist and Brahmin ceremonies, culminating with a procession through Bangkok.

King Maha Vajiralongkorn, left, with Queen Suthida. Credit: PA

Suthida Tidjai has long been linked romantically with the king in the country, having been appointed as a bodyguard after previously working as a flight attendant for Thai Airways, but a relationship has always been denied.

Since joining the king's entourage as a bodyguard she has been appointed as a general in the army.

This is the fourth time father-of-seven Vajiralongkorn has been married, the previous three ending in divorce.

The couple spend their time living between Thailand and Germany, where the king owns a mansion at Lake Starnberg