UPDATE 5-Trump says he may consider sanctions over missing Saudi journalist

Speaking to reporters in Scottsdale, Arizona, Trump said it was too early to say what the consequences for the incident might be.

U.S. President Donald Trump said he might consider sanctions against Saudi Arabia over the disappearance of Saudi journalist Jamal Khashoggi while emphasizing the importance of the U.S.-Saudi relationship.

In Istanbul, Turkish prosecutors investigating Khashoggi's disappearance questioned Turkish employees of the Saudi consulate on Friday, widening the hunt for clues in a case straining Riyadh's alliance with Western powers.

Speaking to reporters in Scottsdale, Arizona, Trump said it was too early to say what the consequences for the incident might be. But he said the U.S. Congress would be involved in determining the American response.

Asked whether sanctions were one of the measures he was considering, Trump said, "Could be, could be."

"We're going to find out who knew what when and where. And we'll figure it out," Trump added.

Khashoggi, a critic of Saudi Crown Prince Mohammed bin Salman, went missing after entering the consulate on Oct. 2 to obtain documents for his upcoming marriage. Turkish officials believe he was killed in the building. Saudi Arabia has denied the allegations.

The U.S. Congress is controlled by Trump's fellow Republicans, some of whom have called for tough action against Saudi Arabia.

"I'm going to have very much Congress involved in determining what to do. ... I will very much listen to what Congress has to say. They feel very strongly about it also," Trump said.

Trump has also been reluctant to imperil major arms deals with Riyadh.

"Saudi Arabia has been a great ally of ours. That's why this is so sad. ... Saudi Arabia has been a great ally, they've been a tremendous investor in the United States," Trump said.

Turkish police searched a forest on Istanbul's outskirts and a city near the Sea of Marmara for Khashoggi's remains, two senior Turkish officials told Reuters, after tracking the routes of cars that left the consulate and the consul's residence on the day he vanished.

Investigators have recovered samples from searches of both buildings to analyse for traces of Khashoggi's DNA.

State-run Anadolu news agency said the Turkish prosecutor's office had taken testimony from 20 consulate employees, and that 25 more people including foreign nationals would be questioned.

The consulate employees questioned included accountants, technicians and a driver, Anadolu said. The investigation is being conducted by the prosecutor's terrorism and organised crime bureau, it added.

Turkey said on Friday it had not shared with any country audio recordings purportedly documenting Khashoggi's murder inside the consulate, dismissing reports it had passed them to the United States.

Turkish pro-government newspaper Yeni Safak has published what it said were details from the audio, including that his torturers severed Khashoggi's fingers during an interrogation and later beheaded and dismembered him.

"We will share the results that emerge transparently with the whole world," Turkish Foreign Minister Mevlut Cavusoglu said.

Trump wrote on Twitter that Secretary of State Mike Pompeo "was never given or shown a Transcript or Video" from the consulate. Pompeo has also said he did not review any recordings.

The disappearance and presumed death of Khashoggi, a U.S. resident and Washington Post columnist, has caused an international outcry and strained relations between Saudi Arabia and Western allies.

(With inputs from agencies.)