ANKARA • Turkish President Recep Tayyip Erdogan yesterday rejected Riyadh's account of the killing of dissident journalist Jamal Khashoggi at Saudi Arabia's consulate in Istanbul, saying the murder was the result of a meticulously planned plot and calling on the Saudi King to hold all culprits to account.

"We have strong indications that this murder wasn't the result of a sudden incident, but rather, was the product of a planned operation," Mr Erdogan told ruling AK Party lawmakers at the Parliament in Ankara.

All responsible, including people "at the very top", should be brought to justice and blaming the killing on "a few security and intelligence" officials will satisfy no one, he said.

Broadcaster CNN Turk reported yesterday that crime scene investigators have found two suitcases and possessions believed to belong to Mr Khashoggi during a search of a Saudi consulate car in Istanbul. However, video footage did not show him carrying belongings when he entered the consulate.

The President's comments, while shedding little additional light on the case, were his first official allegation of murder. Mr Erdogan refrained from implicating King Salman, saying he had no doubts about the elderly royal's sincerity.

But he pointedly did not mention the power behind the throne, Crown Prince Mohammed bin Salman, who has been consolidating power at home.

Mr Erdogan asked a number of pointed questions about the incident. They included why the Saudis took several days to open the consulate's doors to outsiders, the location of Mr Khashoggi's body and the identity of a "local cooperator" who purportedly took the body.

"It shouldn't even cross anyone's mind that this matter will be closed without all of these questions being answered," he said.

Mr Khashoggi, a Washington Post columnist and a critic of the Crown Prince, went into the Saudi consulate in Istanbul on Oct 2 to get a certificate necessary for his marriage in Istanbul.

Turkish officials suspect Mr Khashoggi was killed and dismembered inside the consulate by Saudi agents. Turkish sources say the authorities have an audio recording purportedly documenting the killing of the 59-year-old.

Mr Erdogan made no reference to any audio recording in his speech. But he described yesterday the sequence of events leading to the journalist's killing and said the surveillance system at the consulate was deactivated on purpose.

The Saudis initially said the journalist left the building unharmed but that narrative gradually changed, culminating in an official admission of Mr Khashoggi's death in the hands of Saudi operatives in a fight in the consulate more than two weeks later.

The Saudi version of events has been greeted sceptically by several Western governments, straining relations with the world's biggest oil exporter.

Two sources told Reuters that CIA director Gina Haspel was travelling to Turkey on Monday to work on the Khashoggi investigation.

Saudi Arabia's Cabinet yesterday said it would hold accountable all those behind the murder "no matter who they may be".

Mr Erdogan's speech coincided with the opening in Riyadh of an investment conference boycotted by Western politicians and global business chiefs over Mr Khashoggi's killing. Despite the furore, the kingdom yesterday signed deals worth US$50 billion (S$69 billion) in a sign of its ability to still attract investment. Twenty-five deals in the oil, gas, industries and infrastructure sectors were signed with firms such as Trafigura, Total, Hyundai, Norinco, Schlumberger, Halliburton and Baker Hughes.

The conference was attended by Prince Mohammed, who arrived after he and King Salman met members of Mr Khashoggi's family.

WASHINGTON POST, REUTERS, AGENCE FRANCE-PRESSE