Moscow (AFP) - Reports that Russian intelligence gathered compromising information about US President-elect Donald Trump have stirred memories of the dark art of "kompromat", a Soviet-era form of blackmail used to shame adversaries.
The practice was widely used by the Soviet Union's secret services to squeeze information out of Western diplomats during the Cold War and has left many ruined victims in its wake.
The method -- which sometimes involves tapped phones, hidden cameras and honey traps -- outlived the Soviet Union and continues to be used by the KGB security service's successor agency, the FSB Federal Security Service.
"Secret services throughout the world use this," Mikhail Lyubimov, who long headed the KGB's operations against Britain and Scandinavian countries and is now a writer, told AFP.
"We are not the only ones."
Moscow denied the claims Wednesday that it had gathered compromising material against Trump, with Kremlin spokesman Dmitry Peskov dismissing them as a "total fake" and "an obvious attempt to harm our bilateral relations."
US media outlet BuzzFeed published, without corroborating its contents, a 35-page dossier of memos describing sex videos involving prostitutes filmed during a 2013 visit by Trump to a luxury Moscow hotel, supposedly as a potential means for blackmail.
Many news outlets did not reveal details of the claims, as they could not be confirmed. CNN said the dossier originally came in part from an ex-British MI-6 operative hired by other US presidential contenders to dig up dirt on Trump.
Lyubimov said he thought the claims against Trump were an "invention."
"He wasn't of any interest when he was here," Lyubimov said. "This is simply Obama's farewell jab. This is a great card that will continue to be played against Trump for a long time."
- Diplomat traps -
Although Russia is not the only country that uses blackmail to discredit opponents, Moscow has a long history of successfully targeting foreign diplomats with "kompromat", as well as rival businessmen, politicians and activists.
In the mid-1950s, junior naval attache to the British embassy in Moscow, John Vassall, was secretly photographed with a homosexual partner at a time when same-sex relations were banned in Britain.
The KGB used the compromising photographs to blackmail Vassall to serve as one of its agents
John Profumo, former British government minister whose name became associated with the sex and espionage scandal that forced his resignation in 1963, fell into a similar trap.
He fell for Christine Keeler, a 19-year-old prostitute -- who also happened to be in a relationship with a Russian intelligence officer and the Soviet assistant naval attache in London.
In 1964, France's ambassador to Moscow, Maurice Dejean, was caught having sexual relations with a young Russian woman, leading to his firing by Charles de Gaulle.
Most recently, in 2009, a British diplomat stationed in Moscow resigned after a video showing him with two prostitutes emerged online.
"Blackmail through sex is something as timeless as sex itself," Lyubimov said.
- A 'boomerang' -
The use of blackmail against foreign diplomats has become rarer in the post-Soviet era. In the 1990s "kompromat" was mostly used among Russian politicians and businessman trying to get ahead.
Some of the most famous "kompromat wars" happened in the mid-1990s when powerful Russian oligarchs slugged it out against each other in lucrative battles for the privatisation of Soviet state assets.
Many of those business barons also held media companies that splashed ugly allegations against their opponents at will.
Prosecutor General Yury Skuratov was dismissed in 1999 after a video showing a man resembling him having sex with two women was broadcast on the news.
Alleged footage of Mikhail Kasyanov, a former prime minister turned opposition leader, having sex with a political activist was aired last year by a Kremlin-friendly television channel ahead of parliamentary elections.
Other opposition figures, including politicians and journalists, were targeted in a 2010 series of leaks of compromising sex videos involving a young woman named Yekaterina Gerasimova, who they said was a model recruited by either the FSB or a pro-Kremlin youth organisation called Nashi.
"'Kompromat' is a boomerang of sorts," Lyubimov said. "A person cannot work for a long time under the threat of 'kompromat' and then break down and easily turn into an enemy. It's a dangerous thing."