DAMASCUS, Syria, Oct. 29 - During a United Nations investigation into the assassination of former Prime Minister Rafik Hariri that threatens the power of President Bashar al-Assad, a first cousin who is one of the most powerful businessmen in Syria has left the country.
While it remains unclear why the president's cousin, Rami Makhluf, left - his allies say he is in Dubai, United Arab Emirates, working on the expansion of his business empire - many people with close connections to the ruling Baath Party say his departure underscores the investigation's threat to the Assad family's grip on power.
Already, the United Nations has implicated important Syrians in the killing of Mr. Hariri in February, and the Syrian government has since been searching for a formula to satisfy its international critics without undermining its authority at home.
On Saturday, Mr. Assad announced that he would create a judicial commission to investigate the assassination. Syrian officials hope the move will at least buy them time with the United Nations Security Council, which is scheduled Monday to consider ordering economic penalties until Syria cooperates fully with United Nations investigators.
In Syria, a country of about 18 million people, political and economic power is held by a small circle of people, most with family ties to President Assad. Detlev Mehlis, the German prosecutor investigating on behalf of the Security Council, identified two of the most powerful members of that circle as suspects in the killing - Mr. Assad's brother Maher, who controls the presidential guard, and his brother-in-law, Asef Shawkat, head of military intelligence.
Should the Security Council demand that the two be turned over for trial, President Assad would most probably have to resist or face turmoil in a system that is not governed by strong institutions, but instead by individuals, several experts said.
In this environment, Mr. Makhluf's departure has been seen as a sign that those at the core of the country's power structure recognize their vulnerability, and fear that a showdown with the Security Council could spell disaster for them.
"I think that this is the most important challenge facing Syria in its recent history," said Fayez Sara, a Syrian political analyst and writer. "And if the Syrian government or authorities do not handle the issue well, it can in fact lead to a crisis."
The Makhluf family is at the center of the power structure. It controls a business empire including a bank, the duty-free zones at the border and most of Syria's cellphone service. President Assad's mother is a Makhluf and her brother, Muhammad, is Rami Makhluf's father.
"Most notoriously, the family of Bashar's mother, the Makhlufs, has leveraged its connections to amass a commercial empire, the value of which is estimated to exceed $3 billion," wrote Flynt Leverett, a former C.I.A. Middle East analyst, in his recent book "Inheriting Syria: Bashar's Trial by Fire." "In the process, the Makhlufs have become arguably the single most prominent business family in Syria."
The Makhlufs are so influential, few Syrians will speak about them for attribution. Upon succeeding his father, Hafez al-Assad, five years ago, President Assad spoke of liberalizing the political environment, but Syria remains a police state, and many Syrians believe power has become concentrated in fewer hands than it was before his father's death. Even those who support the government and appreciate the Makhluf family's history of paying relatively high wages declined to be identified.
One well-connected analyst said Mr. Makhluf was asked by the president to leave the country. That could not be independently confirmed. The analyst said that the general public resents the tremendous wealth controlled by the president's family, and that by asking Mr. Makhluf to go, Mr. Assad was signaling his willingness to clean up corruption. When he first came to office, Mr. Assad focused on opening up the economy, but did nothing to break up the vast economic fortunes of those who are in power, not just the Makhlufs, experts said.
"They want people to believe that he has left by orders of the president because there is so much grumbling about the wealth he has acquired," the well-connected analyst said. "It is one of the steps taken to try to restore credibility with the Syrian people."