A Kiev court on Thursday adjourned the treason trial of deposed president Viktor Yanukovych in order to let him testify by video link from his hideout in Russia.
The court said the next hearing will be held on May 18 after an appeal from the defence for the Kremlin-backed former leader, who is being tried in absentia.
Yanukovych fled Ukraine in February 2014 after three months of pro-EU street protests in Kiev culminated in a bloody standoff with anti-riot police in which nearly 100 mostly-unarmed people were shot dead.
Defence attorney Vitaly Serdabs requested Wednesday that Yanukovych be given a chance to testify from Russia so that "objective conclusions" could be drawn.
Prosecutors have charged him with treason, "violating the territorial integrity" of Ukraine and "waging war and aggressive military activities".
The charges refer to Russia's March 2014 annexation of Crimea in the wake of Yanukovych's ouster and his alleged support for the separatist insurgency in the industrial east that has led to more than 10,000 deaths.
Russia is highly unlikely to ever return Yanukovych to its ex-Soviet neighbour. President Vladimir Putin revealed in October 2014 that he had ordered a special operation to smuggle Yanukovych out of Ukraine via Crimea.
But Kiev hopes a guilty verdict will pile more diplomatic pressure on Moscow as it continues backing the three-year insurgency in eastern Ukraine.
The street revolt began when Yanukovych in November 2013 pulled out of a trade and political association agreement with the European Union and instead accepted a $3-billion (2.7 billion euro) loan from Russia to help Ukraine's sluggish economy.
His pro-Western critics called the payment a bribe provided by Putin to persuade Yanukovych not to build stronger ties with the EU and remain in Russia's geopolitical orbit.
Russia's late UN ambassador Vitaly Churkin held up a letter during a March 2014 Security Council meeting that he said Moscow had received from Yanukovych in which the Ukrainian leader asked for the Kremlin's military help.
But Kremlin spokesman Dmitry Peskov said in March that neither Putin nor his presidential administration had ever seen such an appeal.