SHE has in the past been labelled as Moscow’s own Paris Hilton, a Muscovite "It girl", a career celebrity. She hosted a popular TV reality show and co-wrote a book entitled Marry a Millionaire.

Recently, however, Ksenia Sobchak, 35, has been making the news in an altogether more serious vein, having declared herself as a protest candidate in the Russian presidential election next March. She has been active in anti-Putin protests since 2011, but there has been widespread scepticism that she is anything other than a Kremlin-supported decoy, intended to draw attention away from Alexei Navalny, Russia’s high-profile, charismatic anti-corruption campaigner, and to give the election a sheen of legitimacy.

The Kremlin says Navalny is ineligible to stand next March because of his criminal record. Navalny insists his conviction on embezzlement charges was politically motivated.

Vladimir Putin, who has been in power since 2000, is almost certain to be re-elected. As the Economist wrote late last month, Russia’s electoral politics have long been neutered by Putin, “who decides who can and cannot run; the population assumes the role of a television audience with little say over the show’s content.” The magazine went on to say that the Kremlin “is allegedly encouraging Sobchak, to run for president in order to distract attention” from Navalny, a former friend of Sobchak’s, who has been campaigning vigorously for months in the face of harassment and intimidation. He has been sentenced to several spells in prison.

Sobchak has admitted publicly that she has “no political weight” and that “I haven’t earned the right to launch some kind of political programme or stand as a candidate”. The elections were, she added, “unfair”, but it was important to seize opportunities when they arose in order to give voice to discontent. The speculation that Putin had approved her candidacy is, she says, designed to discredit her. “The authorities have decided to suffocate me with affection. It’s a very clever tactic. They’re doing everything to make it look like we’re together,” she said.

One report last week noted that since launching her campaign, Sobchak has breached a number of official political taboos, urging the release of some political prisoners and arguing that Russia had broken international laws by annexing Crimea, which she said was part of Ukraine. She has also spoken publicly about Navalny.

Sobchak’s father was Anatoly Sobchak, a former mayor of St Petersburg and a mentor to Putin. Reports say that, 20 years ago, Putin put in motion a secret operation to evacuate Sobchak from St Petersburg to Paris, at a time when he was ill, and subject to criminal investigations.

An FT interview in 2012 noted that Sobchak had grown up with links to the Kremlin elite. In her teens and early twenties, it added, “she was the rich kid who rolled up to Moscow club openings in BMWs, wearing sable and chinchilla. In her mid-twenties, the socialite aimed for notoriety. She shook her barely-clothed derriere in music videos, posed for Russian Playboy and hosted a foul-mouthed, sex-mad reality TV series called Dom-2. The nadir was a reality show about her life, called Blonde In Chocolate, when she was filmed drunk and falling out of a bejewelled mini-dress as three security men escorted her to bed by the wrists and ankles.”

She now, the FT continued, hosted two “surprisingly hard-hitting interview programmes, grilling opposition members and Kremlin associates”, but some people were sceptical about her transformation. Sobchak herself told the interviewer: “Why was I going around in rhinestones before, and am now wearing a plaid shirt and glasses? It's not a question of fashion. It's a question of time and yourself. The country changed, I grew up, life changed. It's normal."

By the time of the interview Sobchak had become a noted opposition figure and had stood, unsuccessfully, for a seat in the country’s Opposition Coordination Council.

In a new BBC interview she has spoken, in English, of her desire to unite those Russians who are sick of Putin: “I want to be this option to make people come and say, ‘We’re against … We think you are all fake. You’re not ruling the country. People don’t want you to be in power, and this is what reality is," she said.

“I never was part of any alliances with authorities,” she said of her past. “I never took part in any political parties associated with Putin or his system that he built.” Her only link with the President had occurred when she was 10 years old, “playing Nintendo and Super Mario, some guy came with my father and did something to do with the city [of St Petersburg].”

She has also said she will step down if Navalny is permitted to run. Navalny himself has dismissed her as a Kremlin stooge and a “liberal laughing stock". His supporters believe she has split the opposition and has conferred legitimacy on fake elections – charges she rejects.

“I believe in this overturning election point,” Sobchak told the BBC. “I want those elections to be a kind of referendum for trust for Putin, and that people who would vote for my name and against all concept would vote not for me – they would vote against Putin and against his system.”