Uzbekistan's former deputy ambassador to the UK is on trial for treason after claiming to be a spy during an apparent psychotic episode and suicide attempt.

He faces up to 20 years in prison if found guilty in a case that calls into question the Uzbek leadership's attempts to reform the repressive government of late president Islam Karimov. The closed proceedings started on Monday.

Kadyr Yusupov, 67, who was deputy head of mission at the London embassy from 1999 to 2002, threw himself under a train in the Tashkent underground in December but survived with broken ribs and a concussion.

He was detained in the hospital after he told officers responding to the incident that he was a Western spy, but relatives said he was not in his right mind and has suffered periodic severe episodes of schizophrenia.

Previously accused of torture of government critics, the national security service was rechristened the state security service and given a new director as part of president Shavkat Mirziyoyev's efforts to liberalise and open the country for investment after Karimov's death in 2016.

But Mr Yusupov's son Babur, a long-time resident of London, claimed to The Telegraph that security service interrogators had repeatedly threatened to rape his father with a baton and commit sexual violence against female relatives.