The Syrian president said in remarks published Friday that he is adamant his regime will not fall. He also lashed out at the Gulf countries, which he accused of using their enormous oil wealth to try to drive him from power.

Bashar al-Assad's comments came as an opposition group, the National Coordination Body for Democratic Change in Syria, accused the regime of being behind the disappearance of two of its leaders.

Abdul-Aziz al-Kheir and Ayas Ayyash were expected to take part in a conference Sunday in Damascus by some 20 Syrian groups that are calling for Assad to step down. But they disappeared Thursday along with a friend who had picked them up at Damascus International Airport, the group said.

The group's head, Hassan Abdul-Azim, told The Associated Press by telephone that the regime was believed to be behind the disappearance.

Syria's crisis began in March last year with anti-government demonstrations demanding reforms. Syria later became embroiled in a civil war between forces fighting for Assad and those trying to topple him. The violence has killed more than 20,000 people so far, according to the UN.

In the interview with the Egyptian weekly Al-Ahram Al-Arabi, Assad said the rebels "will not succeed" and that a foreign military intervention such as the one that helped topple Libyan leader Muammar Gaddafi will "not be repeated" in Syria.

Assad launched one of his harshest attacks on Saudi Arabia and Qatar, which have been among his strongest critics and backers of the opposition, saying they are trying to influence the region with their money.
"They think their money can buy geography, history and a regional role," Assad said.

"They are giving terrorists weapons and money with hope of repeating the Libyan model," Assad added. "Instead of helping regional stability they are supplying armed elements with weapons and training in order to weaken the Syrian state."

The upheaval in Syria presents an opportunity for the Gulf's rulers to bolster their influence and possibly leave powerhouse Iran without its critical alliances that flow through Damascus. Assad's regime is allied strongly with Iran.

Syria's ties with the Gulf nations have been strained in the past — Assad once called Saudi King Abdullah and other Arab leaders "half men" for being critical of Hezbollah over the 34-day war between the Lebanese resistance group and Israel in 2006.

Assad added that the only way to solve the Syrian crisis is through "dialogue with the opposition" and that the "door for dialogue is open."

Most Syrian opposition groups reject any talks with the regime, saying they will not accept anything less than Assad's departure from power and the dissolving of his regime's security agencies.

Abdul-Azim, the opposition leader, repeated that stance and said the opposition wants a "new regime that represents the will of the people."

He added his group will go ahead with the plans for Sunday's opposition conference despite the disappearance of the two leaders. The gathering will invite European ambassadors and envoys from China and Russia, which back the regime.

Meanwhile, in Syria's northeastern town of Ein al-Arab, a gunman on a motorcycle shot dead a leading Kurdish opposition figure, Mahmoud Wali, also known as Abu Jandi, as he walked out of his office late Thursday, Kurdish activists Mustafa Osso and Ibrahim Issa said. Wali was a senior member of the Kurdish National Council, which includes several Kurdish groups.

Osso said it is still not clear who was behind what he said was a "political assassination."

Accounts of violence are difficult to verify due to tight media restrictions in Syria, conflicting accounts, and the deteriorating security situation for journalists.