Turkey issued an international arrest warrant in April last year for fugitive businessman Faruk Fatih Ozer, who fled with a reported $2.0 billion in investors' assets.
The 2015 deal, known formally as the Joint Comprehensive Plan of Action, aimed to prevent Iran from developing a nuclear weapon something it has always denied wanting to do.
President Erdogan is visiting Ukraine to hold talks with President Zelenskyy and UN Secretary-General Antonio Guterres. Finding a solution to the prevailing crisis in the war-hit country is on the agenda of the meetings.
