Every Sunday Nuri Sani welcomes his old friends around a bountiful Turkish breakfast in Istanbul. But surrounding him now are empty tables on his terrace at his restaurant by the Blue Mosque.

"On a day like this, we should be full," the owner of Şerbethane restaurant said in the city's historic district.

Within a few days of Russia's invasion of Ukraine on Feb. 24, Ukrainians and Russians canceled reservations for trips, disastrous for Turkey where tourism represented 10% of gross domestic product (GDP) before the pandemic.

There had been high hopes for a tourism revival in 2022 and the sector was in desperate need of a boost after the Turkish lira lost significant value last year and inflation soared to over 50% in February.

Visitors from Ukraine and Russia made up over a quarter of all tourists who arrived in Turkey last year, usually opting for the turquoise beaches on the Mediterranean and Aegean, according to Culture and Tourism Ministry figures.

"Russia and Ukraine are very important markets for us," Hamit Kuk of the Association of Turkish Travel Agencies (TÜRSAB) said.

Around 4.5 million Russian and 2 million Ukrainian tourists descended on Turkey last year.

TÜRSAB expected 7 million Russians and 2.5 million Ukrainians this year, but Kuk said it would "likely have to review these figures."

"The war between Russia and Ukraine is making everyone nervous here. Both from a human and commercial point of view," Kuk said.

"Normally, there would be a rush of summer reservations in March. But the demand has stopped," he added.

Sanctions pain

"If it goes on like this, there will be a very serious problem," warned TÜRSAB Chairperson Firuz Bağlıkaya.

"We try to wait as calmly as we can."

In front of the Hagia Sophia Grand Mosque, Russian tourists were rushing to follow their guide, ducking their heads and refusing interviews.

There were even a few Ukrainians, including a young couple from Kyiv who "arrived as tourists and became refugees" and who were now tearfully looking to leave for a third country.

"Maybe the United States?" they asked, wishing to remain anonymous.

The situation is tricky for Turkish travel agents like Ismail Yitmen because of Western sanctions against Russia.

In his office opposite the Hagia Sophia, Yitmen despaired.

"Travel agencies like mine working with Russia are really suffering right now. Taking into account the deposit amount I have paid for hotels, my loss is more than 11,000 euros ($12,000) so far," he said.

If more groups cancel, he could lose between $65,000 and $76,000.

"A group was supposed to arrive in Turkey in two months, but we couldn't receive the money, so it's cancelled. It's because they stopped SWIFT transfers. We had already paid for the hotels."

Several Russian banks were cut off from the SWIFT messaging system, which allows banks to communicate rapidly and securely over transactions.