KIEV, January 17 (RIA Novosti) - Adam Osmayev, a suspect in an alleged plot to assassinate Russian President Vladimir Putin last January who is currently on trial in Ukraine, on Thursday claimed torture and retracted his earlier testimony as having been made under duress.

Osmayev sent his retraction in a letter to Odessa District Judge Viktor Pyslar and Odessa Region Prosecutor Oleksandr Halkin, the Unian news agency reported.

His wife, Anina Okuyeva, presented a copy of the letter to reporters.

Osmayev said he was subjected to physical and psychological harassment during the pretrial investigation, which forced him to confess to the plot.

Ukrainian state security officers hit him repeatedly on the head, put a plastic bag over his head, injected him with narcotic substances and threatened further torture unless he confessed to planning to assassinate Chechen leader Ramzan Kadyrov and President Putin, he said.

Ukrainian law enforcement agencies leveled a host of charges against Osmayev, from planning a terrorist attack to forging documents. Osmayev has only admitted to entering Ukraine on a false passport.

Earlier on Thursday Odessa’s Primorsky District Court adjourned the hearing of Osmayev’s case to February 4, his lawyer, Olha Chertok, said.

Osmayev and a second suspect, Ilya Pyanzin, were detained in the port city of Odessa after a fellow suspect was killed in an apartment explosion there last January. They confessed shortly afterward to planning to murder Putin at the orders of Chechen warlord Doku Umarov. The men were then charged with forming a terrorist group and plotting a terrorist attack.

Pyanzin was extradited to Russia on August 25, 2012.

The news of the attempted plot was released at the height of Putin's campaign to be reelected as president of Russia in the March 4, 2012, election.

Ukraine suspended Osmayev's extradition to Russia pending his appeal to the European Court of Human Rights. The Russian-born suspect, who has renounced his Russian citizenship, has applied for refugee status in Georgia and Finland.

On August 14, a Ukrainian appeals court ordered Osmayev's extradition to Russia. The court rejected an appeal lodged by Osmayev’s defense team and upheld the extradition request from the Ukrainian Prosecutor General’s Office. Osmayev’s defense then appealed to the European Court of Human Rights.