The former Russian oil tycoon said he would not return to Russia, however.
The former oil tycoon spent 10 years in jail on what the West considers trumped-up political charges by President Vladimir Putin's government. He was pardoned Friday by Putin and immediately flew in a private jet to Berlin, where he spoke at a tumultuous news conference near Checkpoint Charlie, one of the main crossing points from East Berlin to West Berlin during the Cold War.
The 50-year-old appeared composed at his first public appearance since his release, saying he shouldn't be viewed as a symbol that there are no more political prisoners in Russia. He added that he would do "all I can do" to ensure the release of others.
"The time that is left for me is time I would like to devote to the activity of paying back my debts to the people ... and by that I mean the people who are still in prison," he said.
However, Khodorkovsky said he would not be "involved in the struggle for power" in Russia.
Khodorkovsky, his shaven prison haircut contrasting with a formal business suit, said he first heard that he could be freed on Nov. 12, when his lawyers told him that former German Foreign Minister Hans-Dietrich Genscher "said President Putin will not make admission of guilt a condition of my release." The veteran German diplomat, whom he repeatedly thanked, had worked for years behind the scenes on his case.
At 2 a.m. on Friday, he said, the commander of the prison colony in northwest Russia where he was being held "woke me up and said I was going home."
Only later did he find out "that the trip was meant to end in Berlin," Khodorkovsky added.
He said the media and Western politicians had played a big role in his securing his release by drawing constant attention to his case, and that helped to keep his spirits up.
"The most important thing for a prison inmate is hope," he said.
Khodorkovsky declined to advise Western governments in their dealings with Putin's Russia, saying they themselves knew best "how they should behave toward someone who is as difficult as the president of my country."
Asked whether he held any ill feelings toward Putin, Khodorkovsky said because his family hadn't been made to suffer while he was in prison he preferred to take a "pragmatic" approach, though he remains sharply at odds with Putin's government.
"Obviously there are things I don't like," he said. "There are rules that need changing."
Khodorkovsky confirmed comments reported by German news agency dpa earlier that he wouldn't seek a leading role in the political opposition against Putin, nor sponsor the opposition. Before his imprisonment, he had publicly challenged Putin's dominance by funding opposition parties and was also believed at the time to have personal political ambitions.
Asked whether he planned to take legal action to reclaim the assets of his dismantled Yukos oil company or return to business in some other way, he demurred.
"My financial situation doesn't require me to work just to earn some more money," he said. "I think as part of my career in business I've achieved virtually everything I'm wanted to achieve."
There has been speculation over what remains of the vast fortune that once made him Russia's richest man. Khodorkovsky was convicted in 2003 for tax evasion and money-laundering in cases that were widely criticized as revenge for his political activities. He faced a second trial and prison sentence in 2010, and was not due to be released from prison until next August.
Asked about his next move, Khodorkovsky said he wasn't sure but that he had a one-year visa for Germany.
"For the time being, my family matters are the most important," he said.
A return to Russia isn't imminent because of the possibility that he could be charged again, said Khodorkovsky.
"At the moment, if I were to go back to Russia, I may not be allowed to leave the country again," he told journalists.
Some in the West had interpreted Khodorkovsky's release, along with an amnesty that covers two jailed members of the Pussy Riot punk band and the 30-member crew of a Greenpeace protest ship, as aimed at easing international criticism of Russia's human rights record ahead of February's Winter Olympics in Sochi, Putin's pet project.
Khodorkovsky said he opposed any boycott of the Winter Games.
"It's a celebration of sport, something which millions of people will celebrate," he said. "Obviously, it should not become a great party for President Putin."