The Presidency of Religious Affairs (Diyanet), Turkey's top religious authority, has announced a nationwide ban on prayer gatherings, including Friday prayers, in the wake of the coronavirus outbreak.

Mosques will remain open to people who want to perform daily prayers, the head of Diyanet, Ali Erbaş, said in a statement Monday.

"Until the danger of spreading the new type of coronavirus disappears, it has become necessary to interrupt prayers with the community in mosques and masjids, especially Friday prayers," Erbaş told a news conference.

Erbaş urged the faithful to pray at home.

As part of the measures against the coronavirus, all passengers returning from abroad since Saturday have been placed under quarantine in dormitories, Health Minister Fahrettin Koca announced Sunday. The dormitories were already empty as Turkey earlier announced a mandatory break for universities and grade schools.

The move came hours before the Interior Ministry ordered the closure of all cafes, theaters, gyms and other similar social spaces beginning Tuesday.

Turkey on Sunday announced the number of confirmed coronavirus cases in the country had risen to 18.

Of the 18 cases, seven were people who returned from European countries and three came from the U.S., Koca said.

The minister urged all citizens to follow self-quarantine protocols if they suspect themselves of contracting the virus.

The government had previously closed schools and universities and suspended flights to several countries. It also quarantined thousands of pilgrims returning from the Umrah pilgrimage to Saudi Arabia, putting them in student dormitories in the capital Ankara and the central Anatolian city of Konya.