Syrian Prime Minister Riad Hijab has defected to the opposition in protest against the “genocide” President Bashar al-Assad is carrying out against his own people, his spokesman says.

“I announce my defection today (Monday) from the regime of killing and terror, and I join the ranks of the revolt,” the former prime minister said in a statement read by his spokesman Mohammed al-Otri on Al-Jazeera news channel.

He said his defection comes at a time “when Syria is passing through the most difficult war crimes, genocide, and barbaric killings and massacres against unarmed citizens”.

Hijab, the highest-ranking official to defect from Assad’s regime, has “become a soldier in the ranks of the soldiers of the revolt,” Otri said.

He said the premier’s defection took “months” to organise and “rebels inside the country have secured this honourable exit for him”.

“He put his life on the line for this revolt … to tell the world that we were forced to be with this regime and the sword was at our necks,” the spokesman said.

“Our information is confirmed through Riad Hijab that the Syrian regime is collapsing and will definitely fall.”

Otri said the premier was in a “safe haven and in safe hands” with 10 relatives and their families, adding that he “will soon appear and talk”.

Opposition Syrian National Council member Khalid Zein al-Abedin told AFP in Amman that Hijab, his family, two ministers and three army officers crossed the border into Jordan on Sunday night.