SIMFEROPOL, Ukraine -- A court in Russian-occupied Crimea has convicted prominent Crimean Tatar leader Ilmi Umerov of separatism after a trial Human Rights Watch called "ruthless retaliation" for his opposition to Moscow's takeover of the peninsula.

The Russian-appointed judges in Simferopol, the Crimean capital, found Umerov guilty on September 27 and sentenced him to two years in a colony settlement, a penitentiary in which convicts usually live near a factory or farm where they are forced to work.

"The case against Umerov was nothing but a sham from the start and today's guilty verdict is a ruthless retaliation for publicly saying that his home should be free," Tanya Cooper, Ukraine researcher at Human Rights Watch, said in remarks to RFE/RL after the court decision.

The judges began reading out the ruling before Umerov's defense team was inside the courtroom.

Speaking to reporters earlier, defense lawyer Mark Feygin expressed hope for a less severe sentence, given a recent UN report that contained scathing criticism of the human rights situation in Crimea under Russian rule.

But the court imposed a sentence that was harsher than that sought by prosecutors, who had recommended a three-year suspended sentence with a ban on all public activities for three years. With a suspended sentence, Umerov would not have been confined to a penitentiary.

Umerov said he would appeal the ruling all the way to the European Court of Human Rights.

"This sentence will not force me to change my convictions," he said.

"I will remain a person who considers that Crimea is the territory of Ukraine that has been occupied by Russia," he added.

Umerov's lawyer, Feygin, said he hoped Western countries would put pressure on Russia to try to quash the verdict. "His dispatch to a prison colony would mean his death," he said of his client.

The European Union called Umerov's sentencing "a serious violation of his human rights, another example of persecution of the Crimean Tatar community."

A statement issued by Maja Kocijancic, a spokeswoman for EU foreign policy chief Federica Mogherini, said the move was "a further and clear illustration of the severe deterioration of human rights on the Crimean Peninsula, as most recently documented by the United Nations High Commissioner for Human Rights in his report published earlier this week."

A UN human rights report issued on September 25 said that Russia's occupation of Crimea had been marked by disappearances and torture, infringements of the Geneva Convention, and violations of international law.

The human rights situation in Crimea "has significantly deteriorated under Russian occupation," the UN Human Rights Office said in the report.

Ukrainian President Petro Poroshenko condemned the sentence as "disgraceful" on Facebook, calling Umerov "a hero of his people against whom Moscow used the worst methods of Soviet-era repression."

Ukraine's Foreign Ministry called the verdict an "illegal and politically motivated sentence" that it said violated Umerov's human rights.

"Russia continues its shameful policy of pressure on the independent leaders of occupied Crimea," the ministry said in a statement.

Umerov, a deputy chairman of the Mejlis, the Crimean Tatars' elected representative body, has been an outspoken critic of Russia's seizure of the Black Sea peninsula from Ukraine in March 2014 and its subsequent crackdown on Crimean Tatars.

Russia's Federal Security Service (FSB) detained Umerov, who suffers from diabetes and Parkinson's disease, in May 2016 in Crimea and charged him with separatism.

He was confined in a psychiatric hospital in August 2016 by the Russian-imposed authorities in Crimea, a decision condemned by Human Rights Watch as "an egregious violation of his rights."

"They tried to scare Umerov with criminal prosecution, forced him to undergo a humiliating psychiatric examination, refused him medical care he required for his health condition, yet he did not abandon his peaceful, principled opposition to Kremlin's abuses in Crimea," Cooper said.

Speaking at the trial on September 20, the 60-year-old Umerov said that the charges against him had a single goal, "which is to punish those who oppose the annexation."

"I call the annexation an annexation and the authorities established [by Russia] occupation authorities," he told the court.

Umerov said he considered himself "only a citizen of Ukraine."

The Moscow-based human rights group Memorial has called the case against Umerov "illegal and politically motivated."

The charges stem from a March 2016 live interview with the Crimean Tatar TV channel ATR, which was later posted on YouTube. Russian authorities shut down the station in April 2015 and it relocated to Kyiv.

Umerov said the translation of the interview into Russian from Tatar was poorly done and distorted his remarks.

Cracking Down On Crimean Tatars

The Russian authorities have outlawed the Mejlis after deeming it extremist, part of what rights groups and Western governments say is a persistent campaign of oppression targeting Crimean Tatars and other citizens who opposed Moscow's takeover.

Another Mejlis deputy chairman, Akhtem Chiygoz, was convicted of organizing an illegal demonstration and sentenced to eight years in prison on September 11 after what Amnesty International called a "sham trial."

Umerov's conviction follows a similar ruling in Crimea on September 22 against RFE/RL contributor Mykola Semena.

The U.S. State Department on September 25 expressed concern over the conviction of Semena, who was handed a 2 1/2-year suspended sentence, saying it was "based on the fact that Mr. Semena had criticized Russia's occupation and attempted annexation of Crimea in his writing."

Following the ouster of a Moscow-friendly Ukrainian president in February 2014, Russia seized control of Crimea by sending in troops and staging a referendum deemed illegitimate by at least 100 countries in the United Nations.

With reporting by Reuters