Diplomatic fallout over journalist Jamal Khashoggi's murder appears to be slowing the flow of high-rolling Saudis to Turkey, as calls grow within the oil-rich kingdom to boycott the holiday magnet.

The two Sunni Muslim powers have a longstanding geopolitical rivalry, but relations plumbed new lows after Khashoggi's killing in October in the Saudi consulate in Istanbul, which tainted Crown Prince Mohammed bin Salman's global image.

Each year hundreds of thousands of Saudi tourists visit Turkey, thanks to its milder climate, turquoise waters and status as a crossroads between East and West.

But tensions over the journalist's murder are feeding into growing calls by nationalists and pro-government media to boycott Turkey, potentially hitting its already strained economy.

"Don't go to Turkey" and "Turkey is not safe" are just some of the headlines that have popped up, with multiple media outlets running hostile stories in recent months.

Many, including Al-Arabiya, have splashed official warnings from the Saudi embassy in Ankara about rising passport theft and petty crime.

The apparent scaremongering seems to be working, since the Turkish tourism ministry reported Saudi visitor arrivals dropped more than 30 percent in the first five months of 2019 compared to the same period last year.

A travel agency in Riyadh reported a similar fall in bookings to AFP, although Saudi tourism authorities did not respond to a request for comment.

"I care about safety," a young Riyadh resident told AFP, explaining why he was likely to avoid Turkey.

'Boycott call'

Saudis, who are also among the top property buyers and investors in Turkey, spend an average of $500 (450 euros) a day as tourists in the country, significantly higher than European visitors, according to a 2018 study by Riyadh's King Faisal Center for Research and Islamic Studies.

Appeals for a boycott of Turkey are not limited to tourism.

A video predating Khashoggi's murder that showed Riyadh's influential governor Faisal bin Bandar declining an offer of Turkish coffee recently resurfaced on social media, triggering a call for a boycott of Turkish products.

Ajlan al-Ajlan, chairman of the Riyadh Chamber of Commerce and Industry, has been particularly strident.

"As the Turkish leadership and (President Recep Tayyip) Erdogan continue their hostility and target the kingdom's leadership, we call more than ever before to boycott them... in all areas -- imports, labour and dealings with Turkish companies," Ajlan wrote on Twitter last month.

Observers have drawn parallels with how Saudi Arabia flexed its financial muscle by adopting punitive measures in recent diplomatic disputes with Canada, Germany and neighbouring Qatar, now under a Riyadh-led economic blockade for two years.

Turkish officials were the first to report Khashoggi's murder and have continued to press Riyadh for information on the whereabouts of his dismembered body, which remains missing.

The CIA has reportedly said the murder was likely ordered by Prince Mohammed, a charge Saudi Arabia vehemently denies.

Last month, Prince Mohammed -- heir to the Arab world's most powerful throne -- warned against "exploiting" the murder for political gain, in what appeared to be a veiled attack on Erdogan.

Even before the killing, Riyadh had testy relations with Ankara, a key backer of Doha and accused of supporting Islamist groups including the Muslim Brotherhood.

Saudi Arabia views the Brotherhood as an existential threat.

The boycott rhetoric could not have come at a worse time for Turkey as it battles an economic crisis.

"The already suffering Turkish real estate market could be further damaged by a mass exodus of Saudi property holdings," Hussein Ibish, a scholar at the Arab Gulf States Institute in Washington, told AFP.

"That's another big gun Riyadh hasn't fired yet."

So far however the data does not show damage to the Turkish property market, with home sales to Saudi citizens from January to May 2019 up at 992, compared with 977 over the same period last year.

'Don't go to Turkey'

The tensions come as Saudi Arabia -- hit by a downturn in oil prices -- seeks to boost domestic spending, reversing a decades-long trend that has seen citizens splurge cash overseas.

"Saudi Arabia is hitting two targets with one bullet -- stop Turkey from benefitting from Saudi tourists and convince Saudis to spend their money domestically," said Quentin de Pimodan, a Saudi expert at the Greece-based Research Institute for European and American Studies.

And Abdullah, a 39-year-old Riyadh-based academic, laughed off the travel warnings, telling AFP his family planned a Turkey visit this year.

"Saudis love going to Turkish restaurants" in their own country, said Abdullah, who requested his full name be withheld.

"When they finish eating, they write on Twitter: 'Don't go to Turkey'."