Mikhail Khodorkovsky has said after his release from prison that he had sought a pardon from Russian President Vladimir Putin for family reasons and did not admit guilt.
In a statement
on December 20, Khodorkovsky said, "The issue of admission of guilt was not raised."
Khodorkovsky, a former oligarch and Kremlin critic, was released from prison in the northwestern region of Karelia earlier on December 20 after he was pardoned by President Vladimir Putin on "humanitarian grounds."
Hours after his release, Khodorkovsky arrived at Berlin's Shoenefeld airport, where he was met by former German Foreign Minister Hans-Dietrich Genscher.
Chancellor Angela Merkel said Genscher had played a role "behind the scenes" to secure Khodorkovsky's release.
"I don't want to assess the reasons for it now. At any rate, firstly, it was important not to forget him and to keep drawing attention to the issue, and secondly, there was a window of opportunity that was used," Merkel said. "This is a good message."
Prison officials said in a statement that Khodorkovsky had petitioned to be allowed to leave the country to see his mother, who recently underwent medical treatment in Germany but has since returned to Russia.
Both Khodorkovsky's parents are expected to fly to Germany on December 21.
Khodorkovsky's father, Boris, told reporters that the family felt "joyful" upon hearing of his son's release.
He headed the country's largest oil company when he was arrested in 2003 and charged with tax evasion. He was convicted two years later. In 2010, he was convicted of embezzlement at a second trial.
Supporters say his financial support for opposition parties upset the Kremlin and that his prosecution was politically motivated.
His prison term had been due to expire at the end of August 2014.
Critics say that by Khodorkovsky's release and a wide-ranging amnesty this week, Putin may be trying to ease criticism of Russia's human rights record ahead of the Winter Olympics in Sochi in February 2014.
Russian businessman and opposition politician Mikhail Prokhorov said he was glad that Khodorkovsky was "finally" released.
WATCH: Why Has Khodorkovsky Been Released?
Prokhorov, who finished third in the 2012 presidential election, said he would "certainly call him" after Khodorkovsky spends some time with his family.
Later on December 20, U.S. Secretary of State John Kerry welcomed Khodorkovsky's release.
A written statement from Kerry noted that Washington has repeatedly expressed concerns about what it described as “due process violations and selective prosecution in Russia, including against Khodorkovsky and his business partner Platon Lebedev, who remains in prison.”
The statement said Washington strongly encourages Russia to pursue judicial reforms.
Lebedev Won't Seek Pardon
A lawyer for Platon Lebedev -- a close associate of Khodorkovsky's who was also convicted of tax evasion and sentenced to a nine-year term in 2005 -- said his client will not ask Putin for a pardon.
Aleksei Miroshnichenko said after meeting with Lebedev in prison that Lebedev was "very glad" to hear about Khodorkovsky's release. But he said Lebedev will not ask for a pardon.
Lebedev, 57, was the head of Bank Menatep, a company created by Khodorkovsky that held a controlling interest in his Yukos oil company.
Miroshnichenko said Lebedev was determined to have his conviction overturned, adding that they had discussed appealing to the chairman of the Russian Supreme Court.
Lebedev is to be released from jail in May.
IN PICTURES: Khodorkovsky: From Young Tycoon To Graying Inmate
Mikhail Khodorkovsky in 1992, when he was chairman of the board of directors of Menatep bank
Khodorkovsky with his family in October 1992
Khodorkovsky and his family at their dacha in 1992
Khodorkovsky, Russian Prime Minister Viktor Chernomyrdin (center), and Fuel and Energy Minister Sergei Kiriyenko (right) during the signing of a memorandum of intention to merge the Yukos and Sibneft companies on January 6, 1998
Khodorkovsky meets with Russian President Vladimir Putin in March 2002. Khodorkovsky challenged the Kremlin's authority by funding NGOs and opposition parties, lobbying to privatize the state-owned oil pipeline monopoly, and accusing Kremlin officials of corruption.
Khodorkovsky speaks at the Yukos headquarters in Moscow in June 2003, months before his arrest on fraud and tax evasion charges.
Russian police escort the former Yukos oil chief to a courthouse in Moscow on December 23, 2003.
Khodorkovsky supporters protest outside a Moscow court on January 15, 2004. Many Russians see him as a political prisoner jailed for political ambition and his criticism of President Putin. Amnesty International considers him a prisoner of conscience.
Khodorkovsky and Platon Lebedev hear the verdict in a Moscow court on May 16, 2005.
Khodorkovsky at a hearing at the Chita Regional Court in October 2008. During his imprisonment, Yukos was broken up and sold off, mostly into state hands.
Supporters rally on August 27, 2009, as prosecutors presented new charges against Khodorkovsky.
Khodorkovsky and Lebedev are escorted to a hearing in Moscow on January 11, 2010.
Elena Lukyanova (left), a lawyer for Khodorkovsky, and his daughter Anastasia Khodorkovskaya attend "Znamya" magazine's literary award ceremony in January 2010, where Khodorkovskaya received an award on her father's behalf for his "Dialogues With Lyudmila Ulitskaya."
The former CEO's mother, Marina Khodorkovskaya (right), his wife Inna (left), and his daughter Anastasia walk out after a court hearing in Moscow on December 30, 2010. A judge sentenced Khodorkovsky to additional prison time on new charges of financial crimes.
Khodorkovsky's book "Articles. Dialogues. Interviews." is presented in Moscow in January 2011.
Khodorkovsky and Lebedev stand in the defendants' box during a hearing in Moscow in May 2011.
Police detain a Khodorkovsky supporter during a gathering in central Moscow in June 2011.
Activists in London send a birthday message to Khodorkovsky in 2012. On June 26, 2013, he celebrated his 50th birthday in a remote prison colony near the Arctic Circle.
Members of a pro-Kremlin youth group wear masks representing anti-Putin opposition leaders during a demonstration called "Send them to join Khodorkovsky as guests!" on the occasion of the jailed businessman's 50th birthday.