People walk in the snow as they get out of a bus during snowfalls in Istanbul on January 7, 2017. A heavy snowstorm paralysed life in Istanbul with hundreds of flights cancelled and the Bosphorus closed to shipping traffic. (Xinhua/AFP Photo)

ISTANBUL, Jan. 7 (Xinhua) -- A snowstorm is paralyzing people's normal life in Turkey's largest city Istanbul on Saturday, halting flights, public transportations and sea traffic.

Around 400 flights, including domestic and international ones, have been cancelled at the city's Ataturk and Sabiha Gokcen airports scheduled for Saturday and Sunday.

The highway in the north of the metropolis was closed, with seven trucks reportedly piled up due to heavy snowfall in the early morning.

Meanwhile, all the ferry services providing shuttles between the European and the Asian parts of the city were called off for Saturday.

In addition, the authorities closed the sea traffic on the Bosporus Strait for both ways on Saturday morning.

Meteorology experts warned that the snowfall is expected to reach 20 centimetres across the city, urging citizens to take necessary precautions against icing on the roads.

The western and central parts of Turkey are also expected to be hit by "an extreme cold wave" hailing from the Balkans on Saturday.