Abdulrahman Tayeb, a Yemeni doctor, was shocked when his hospital in southern Saudi Arabia told him his contract would not be renewed, leaving him with a difficult choice: go home to a nation at war or try to find work in another country.

He is not alone. Hundreds of medical staff, academics and other professionals in the kingdom's southern region bordering Yemen have in recent weeks been told they are being let go, several Yemenis told Reuters.

The exact number is not known. Staff said they were not provided justification for government orders to stop renewing contracts of Yemenis.

There has been no official explanation and Saudi and Yemeni authorities did not respond to Reuters requests for comment. Yemeni sources who spoke to Reuters said they did not know why the dismissals were happening and were unwilling to advance any theories.

A Saudi analyst, speaking on condition of anonymity, said the move aimed to free up jobs for citizens in the south as part of efforts to tackle Saudi unemployment of 11.7%, and was also driven by security considerations in areas near the war, in which a Saudi-led coalition is fighting Yemen's Houthi group.

A Yemeni government source, speaking on condition of anonymity due to political sensitivities, said the directives could affect "tens of thousands" of Yemenis, including labourers. The source did not know why the orders were issued.

"All the Yemeni doctors working in government hospitals (in the south) were told our contracts would not be renewed," said Tayeb, 40, who comes from Ibb in Yemen and whose wife and two children are with him in Saudi Arabia.

Tayeb, who declined to name the hospital where he has worked for six years, said his employer informed him on Monday that the labour office instructed them to halt contract renewals and provide two months notice. Tayeb's contract expires in December.

"We are shocked by this because Yemenis avoid problems, especially with the war because they have no other options to make a living," he told Reuters.

A document from the Saudi Health Ministry dated July 27 and addressed to a hospital in Al Baha in the southwest, an image of which was seen by Reuters, only referenced instructions to "stop issuing new contracts or renew existing contracts for Yemenis".

'REAL CRISIS'

Saudi Arabia hosts 2 million Yemeni workers, according to the Sanaa Center for Strategic Studies. It is unclear how many are in the south.

Most send money home where prospects are bleak due to the war. The World Bank estimates one in 10 people in Yemen rely on money transfers for basic needs.

Remittances are also an important source of foreign currency for Yemen, whose government is struggling to pay public sector wages.

The source in Yemen's Saudi-backed government said President Abd-Rabbu Mansour Hadi had in recent days raised the issue with Saudi deputy defence minister Prince Khalid bin Salman and further discussions would be held by foreign ministers.

Yemeni Doctors in Diaspora estimates that hundreds of Yemenis at universities and health institutions in southern Saudi Arabia were hit by "mass terminations", said Hamdi Alhakimi, secretary-general of the Netherlands-registered body.

"Our fellow doctors and academics are now facing a real crisis because it is sudden," Alhakimi told Reuters. "We still hope they will be given enough time to find suitable employment in other safe countries."

Several Yemeni professors who spoke with colleagues at universities in the south told Reuters that Najran University was ending the contracts of 100 Yemenis. Around 200 staff at other southern universities were being axed, some said.

An Aug. 8 document from Najran University seen by Reuters, cited "requirements of national interest" in a notification of termination for a Yemeni assistant professor effective Aug 14. It said the decision was approved by the head of the institution on July 27.

The notification offered two months' salary on top of any dues, including end of service gratuity, and a ticket home.

The university did not respond to a request for comment.

FUTURE UNCERTAIN

Ahmad Khalil, 31, who has worked in the contracting industry in Najran for nearly 11 years, said his boss was instructed by the region's secretariat to end the contracts of Yemenis.

"I don't know what awaits me and thousands like me," said the father of two whose family is in Taiz in Yemen.

Some still hope they will not be forced to return.

Accountant Abdullah, who supports three children back home, said his firm in Jazan promised to try to relocate him and seven other Yemenis to other branches in the kingdom.

"Until today the owner is reassuring me," he said. "But I am still worried."