Engaged couples should refrain from flirting, holding hands and "other behaviours that are not endorsed by Islam," Turkey's religious affairs agency declared Monday.
Answering the question "is it appropriate for those who are engaged to be married to be able to see each other?", the agency, known as Diyanet, set out where the limits lay for those who plan to tie the knot in overwhelmingly Muslim Turkey.
"There is no harm in engaged couples meeting to get to know each other, as long as they follow the rules of privacy," it said in a statement on its website.
"But engaged couples need to refrain from flirting, living together, staying together tete-a-tete in a way that could give rise to gossip, holding hands and other behaviours that are not endorsed by Islam," it added.
While many Turks embrace European lifestyles in Istanbul, the Aegean coast and Ankara, traditional Islamic values and religious conservatism hold sway in much of the country.
In many areas, sex before marriage is not only a taboo but simply out of the question.
Turkey's religious affairs agency Diyanet was established in 1924 to oversee religion in the modern secular Turkish Republic following the abolition of the Islamic Caliphate in the wake of the collapse of the Ottoman Empire.
One of its duties enshrined in the constitution is to enlighten the public about religious values.
It frequently issues directives on advice about moral behaviour. But in the officially secular state these have no legal weight.
Critics complain that Turkey has seen a creeping Islamisation under the Islamic-rooted rule of President Recep Tayyip Erdogan, formerly prime minister, that has undermined the secular principles of the modern state set up by its founder Mustafa Kemal Ataturk.
But the government insists it is merely allowing greater religious freedoms to devout Muslims that had been denied in the past.