Latvia has accused Belarus of a serious provocation over the treatment of one of its diplomats.
Belarus was widely criticised for silencing the opposition
Belarus state television on Sunday showed what appeared to be hidden camera footage of gay sex, claiming the Latvian diplomat was involved.
The Latvian Foreign Minister, Artis Pabriks, told the BBC News website the video was an "unprecedented attack" on the diplomat, aiming to humiliate him.
Mr Pabriks said Belarus was avoiding his demands for an explanation.
He said that he had not seen the film, but that it was some kind of compilation, possibly made with hidden camera.
"It is in breach of the Vienna Convention, because it was a violation of the private space of our diplomat."
"I think that it is not clear what exactly the Belarussian position is at this moment, because they are avoiding to give us any explanation."
"There is no co-operation whatsoever from the Belarussian side," he added.
He did not name the diplomat, who has returned to Latvia.
A week ago, before the controversial footage was aired, Belarus police had raided the Latvian diplomat's private residence.
Belarus TV claimed that pornographic material was found during the search.
Latvia denies this and says the video cassettes seized by the police in Minsk contained recordings of Belarus TV news bulletins.
The Belarus Interior Minister, Vladimir Naumov, was quoted by the Russian news agency Itar-Tass as saying a criminal case had been opened against the Latvian diplomat.
Mr Pabriks told the BBC "this is a very strong provocation which shows what kind of justice system exists in this dictatorship".
Latvian newspapers say the diplomat, who was second secretary at the embassy in Minsk, was involved with opponents of President Alexander Lukashenko.
"It is not a secret that Latvia is supporting democracy in Belarus," Mr Pabriks said.
He added that he was waiting for an official response from the authorities in Minsk and was demanding an apology.