Moscow, Russia (CNN) -- Russia's most famous prisoner, and once its richest citizen, says the latest corruption charges against him are designed to prevent his release from jail.
Mikhail Khodorkovsky, head of the giant Yukos oil company, has been jailed since his arrest, as his private jet was about to take off, in 2003. He was charged with fraud and tax evasion and subsequently sentenced to nine years behind bars. A Moscow court later reduced the sentence to eight years.
At the time of his arrest Khodorkovsky had been funding opposition political parties and considered running for public office himself.
He claims his trial was part of a Kremlin campaign to destroy him and take the company he built from privatization deals of the 1990s. The Kremlin has denied this.
Yukos, once the country's biggest oil producer, eventually went bankrupt in 2006 as a result of a $27.5 billion back-tax bill. A Russian court also ordered Khodorkovsky and his partner to pay about $600 million in back taxes.
But in March last year, when Khodorkovsky and his business partner Platon Lebedev, who was also arrested in 2003 and sentenced to eight years, had only two years left on their sentences, they went on trial on new charges of embezzlement and money laundering.
If convicted, they face up to an additional 22 years in prison
In an exclusive interview with CNN, Khodorkovsky maintained his innocence, insisting it is the charges that are fraudulent.
CNN was denied access to the former tycoon but managed to get written questions to him in his jail cell and he was able to respond.
Why have these new charges been brought against you? Do you suspect political motives?
The new charges have been brought to prevent my release from prison. They are undoubtedly politically-motivated since they have no merit whatsoever. To date, the prosecutors have failed to explain where they got the idea that all the oil produced by Yukos had been stolen. And that is exactly what I have been accused of.
Are you simply defending yourself and your former business, or is there a bigger principle at stake?
It was a painful experience for me to see my perfectly functional company laid to waste. However it is all history now. It is common knowledge today that things like a ban on businesses to finance independent opposition [parties], widespread illegal takeovers of property in Russia, and a manifold increase in corruption-motivated arrests of businessmen (their businesses are then seized), all began with the Yukos case.
Since Yukos was first seized, the cost of corruption in the [Russian] economy has grown from $30 billion to $240-300 billion. My trial is both a landmark and a symbol for this country.
Has your time in prison served any positive purpose?
At a certain point in my life I realized that I personally needed to do something to help build civil society in this country. However it was difficult for me to break free from what was a comfortable business routine, both psychologically and in terms of the public's perception of me. In that particular sense, prison has given me a chance to stop and rethink my values.
To what extent has this become a personal battle between you and Vladimir Putin?
Clearly, Putin finds me more than disagreeable. It's difficult for me to say to what extent my persecution and prosecution are based on political calculations, self-interest, or emotion. As for me, my career in business has taught me to keep my emotions under control.
What does your legal situation say about the rule of law in Russia?
There is not one serious-minded individual in Russia right now who would tell you that this trial is lawful. There is talk of whether such methods of achieving political goals are acceptable, and whether the goals are appropriate in the first place.
That the motives are political is no longer -- and hasn't been for a long time -- a subject for discussion. The legally sophisticated part of [Russian] society has also reached a consensus that charges against me are knowingly absurd. Therefore even answering a question about rule of law would be redundant.