The announcement made waves in the former Soviet republic and across its border with Russia.
Latvia's Current Foreign Minister Edgars Rinkēvičs greats NATO Secretary General Jaap de Hoop Scheffer and his wife during a 2006 visit.
Anda Kukemilka "Tevijas Sargs" / Via nato.int
Rinkēvičs confirmed to Latvian TV later that evening that his Twitter account had not been hacked and that he is gay.
The news caused a furor within the former Soviet republic and in the region. Latvia shares a border with Russia and has a large Russian-speaking population that gets much of its information from media across the border. A group of social conservatives led by the controversial pro-Russian activist Vladimir Linderman is currently gathering signatures in an effort to place a referendum on enacting a Russian-style "homosexual propaganda" ban on the ballot.
Speaking on Latvian radio Friday, Linderman said the revelation amounted to propaganda.
"Who cares what Rinkēvičs does in the bedroom? But if he announces it publicly, then he is propagandizing a certain ideology," he said.
Linderman also said coming out as LGBT is a "political trend" and that it had secured Rinkēvičs political longevity.
"Now Rinkēvičs won't be removed from his post as minister, due to the fear of criticism from the West," he said. "The most powerful country in the world has legalized same-sex relationships. All ministers will say they're gay, thus recognizing the dominant ideology."
Russian media reports highlighted claims that the 41-year-old minister lives with his mother and harped on Rinkēvičs's creation of a "blacklist" of Russian celebrities barred from visiting Latvia due to their position on the Ukraine crisis. Among those banned is actor Ivan Okhlobystin, who has called for burning LGBT people alive.