Turkey says the country has witnessed a serious drop in the number of foreign visitors this year, amid growing security concerns in the recent past.

Figures from the Turkish Tourism Ministry released on Wednesday showed that over the past six months, foreign arrivals fell by 2.25 percent to 14.89 million people.

The data show the greatest fall was in the number of tourists from Russia, with a drop of nearly 25 percent.

The ministry added that the outlook for the rest of the year remains gloomy.

Tourism plays a major role in the financing of Turkey’s large current account deficit.

The figures were released days after Ankara started airstrikes allegedly against positions of the Takfiri ISIL terrorists in northern Syria and the Kurdish Workers' Party (PKK) in Iraq.

In recent months, Western countries including the United States, Britain, and Germany have issued travel advisories to their citizens visiting Turkey.

The US embassy in Turkey warned its citizens traveling to the country to “maintain a high level of vigilance” by avoiding spontaneous demonstrations or gatherings and being aware of their surroundings.

It also warned US citizens to avoid traveling to southeastern Turkey if possible.

Following a deadly bombing on July 20 in the border town of Suruc, which killed 32 people, Ankara granted Washington permission to use its bases to attack ISIL militants in Syria. Turkey blamed ISIL for the blast in Suruc.

On Wednesday, the Turkish government gave its formal approval for the United States to use the Incirlik air base in southern Turkey for the attacks against ISIL.

"The cabinet has signed the decree," said a Turkish Foreign Ministry official, adding that the air base can be used by the US against ISIL "anytime."

After the bombing in Suruc, a number of Turkish policemen and soldiers have been killed in attacks attributed by Turkish media to the PKK.

The Turkish cities of Istanbul and Ankara have also witnessed several anti-government protests since.