Turkish citizens living abroad have started casting ballots for Turkey's April 16 referendum on ushering in a system that would boost the president's powers.
Voting began Monday at airports and border gates in Turkey as well as in Turkish diplomatic missions in some European countries.
The government-proposed changes that are being voted on would give executive powers to the presidency and abolish the post of prime minister.
President Recep Tayyip Erdogan, who has long pushed for the changes, insists a stronger presidency would lead to greater prosperity. Critics fear the changes will concentrate too much power in the hands of the president without the necessary checks and balances.
Close to 3 million expatriate Turks are eligible to vote — nearly half of them in Germany.