Ukraine’s president has stripped four people of citizenship, including a Kremlin ally transferred in a prisoner swap.

President Volodymyr Zelenskyy has revoked the Ukrainian citizenship of four political figures, including pro-Kremlin Viktor Medvedchuk, who was transferred to Russia last year in a prisoner swap deal.

Medvedchuk, a close ally of Russian President Vladimir Putin, headed a banned pro-Russian party the Opposition Platform

For Life in Ukraine and was facing treason charges before being transferred to Moscow in September. He was captured in April by Ukraine’s special services

He met Putin for the first time in 2003 and managed the election campaign of Viktor Yanukovich, a fiercely pro-Moscow presidential candidate.

Yanukovich’s victory in the 2004 vote sparked the Orange Revolution, Ukraine’s first pro-Western revolt, whose organisers accused Medvedchuk of rigging the vote.

His unimpeded escape when Russia invaded Ukraine in February was seen as a sign of the weakness of Zelenskyy’s government amid the chaos and uncertainty of the war’s first days.

He was one of more than 50 prisoners handed over to Russia in September in exchange for 215 Ukrainian imprisoned soldiers.