LONDON, Dec. 25 -- Indonesia has reportedly lodged a formal complaint with the United Kingdom after a provocative act by British adult film actress Tia Emma Billinger, also known as Bonnie Blue, at the Indonesian Embassy in London was deemed to have desecrated the national Red and White flag.

Foreign Ministry spokesperson Yvonne Mewengkang said the incident occurred on December 15 and was widely circulated on social media, prompting the embassy to report the matter to the UK Foreign Office and local police, according to Indonesiannews agency Antara.

Mewengkang reportedly said Indonesia regretted the incident and stressed that the national flag symbolises the country's sovereignty and dignity and must be respected at all times, including...