Bashar Assad's recently-appointed prime minister has defected to join the "revolution," further undermining the president’s grip on power as Syria’s bloody uprising rages on.

Riad Hijab, who was appointed to the prime minister's office just two months ago, is said to have fled the country with several members of his family.

Initial reports said that Hijab had crossed the border into Jordan have since been denied on Jordanian State TV.

But in a statement delivered from Amman, Jordan on al Jazeera TV, a Hijab spokesperson said the PM had indeed quit Assad's "terrorist, murderous regime," to become "a soldier of this holy revolution."

Hijab is the highest-ranking regime official, and the first cabinet minister, to have quit Assad's regime. There are reports he is not the only one, however, amidst word two other cabinet ministers had fled alongside him and a third, Finance Minister Mohammad Jalilati, was arrested while attempting his own escape.

Syrian state TV denied reports Jalilati had been detained, and there has been no confirmation from Syria that any other ministers had fled.

Syria has already seen its ambassador to Iraq and more than 30 army generals defect from the regime.

Other recent setbacks to Assad's regime include the deaths of four of his top security aides -- including the defence minister and his brother in law -- in a rebel bombing of state security headquarters in Damascus on July 18.

And just hours before word of the latest defections grabbed headlines worldwide, a bomb ripped through the Syrian state TV headquarters in Damascus, wounding three and cementing the rebels’ ability to strike in the capital despite a concerted military push in the past week to establish control.

Monitoring developments from Jerusalem, CTV's Martin Seemungal said the fact this latest blow extends into the highest echelons of Assad's government sends a strong message about his weakening authority.

The impact of Hijab's defection is more symbolic than actual, however, as Seemungal notes the prime minister was not a member of the minority Alawite community of which Assad and others in his government with the real klout are.

Instead, Hijab is ethnically part of Syria's Sunni majority which has propelled the uprising that has claimed at least 19,000 lives since it began 17 months ago.

"What this does is lay bare the divide between the Alawites and the Sunnis," Seemungal told Â鶹´«Ã½ Channel.

According to Hijab spokesperson Mohammad Otari, rebels from the Free Syrian Army and their supporters had been secretly helping Hijab plot his escape since he was appointed prime minister two months ago.

"The criminal Assad pressed him to become a prime minister and left him no choice but to accept the position. He had told him: `You either accept the position or get killed,'" Otari told The Associated Press, explaining that Hijab and his family are headed to Qatar.

Otari would not confirm Hijab's whereabouts in the meantime, saying only they were all in a "safe place."

Calling on others to follow Hijab's example, opposition Syrian National Council spokesperson George Sabra saluted the move.

"He has finally discovered that this regime is an enemy of its own people and is destined to fall, and he chose to join the ranks of those who defected before him," Sabra told AP.

"This will trigger a chain of other defections by Syrian senior government and security officials," he added. "The Syrian regime is drowning and this is the clearest sign yet."

A senior U.S. official travelling with U.S. Secretary of State Hillary Clinton in Johannesburg, South Africa echoed those comments in a call for other senior members of government and the military to break from Assad's "crumbling" regime.

But Seemungal said, in light of Hijab's high-profile flight, that may now be easier said than done.

"The big question now is, after a defection like this, it may be much more difficult for other high-ranking Sunnis to get out of Syria," Seemungal said, suggesting that others considered a "flight risk" will likely be watched more closely now than ever before.