An Egyptian psychiatrist jailed in Saudi Arabia was sentenced to prison on terrorism charges following an "unfair trial" triggered by a salary dispute, Human Rights Watch said Thursday.

Sabri Shalabi, 66, was taken from his home in the coastal Saudi city of Al-Wajh by plainclothes police officers in January 2020 and last year was hit with a 10-year prison term over alleged links to the outlawed Muslim Brotherhood, according to the New York-based rights group.

But "Saudi prosecutors based the charges largely on forced confessions and apparently in retaliation for a work-related dispute," HRW added.

Saudi Arabia and several other Gulf states view the Muslim Brotherhood as a "terrorist" organisation.

Citing a source close to the family, HRW said Shalabi had told his relatives he was being prosecuted for "expressing sympathy with the Muslim Brotherhood and voting for Mohamed Morsi", the late Islamist leader who won Egypt's 2012 elections.

Saudi officials have not responded to requests for comment on Shalabi's case.

Shalabi, who was employed by the Saudi health ministry between 2006 and 2019, had won a court case against the authorities to settle years of unpaid compensation before he was formally charged.

HRW said the accusations he had faced highlight Saudi Arabia's abuse of counterterrorism laws to silence challengers.

"Saudi Arabia's record of politically motivated prosecutions raises grave concerns that Sabri Shalabi may have been targeted in reprisal for claiming money the government owed him," said HRW researcher Joey Shea.

"The Saudi legal system shows no sign of halting its use of vague provisions of the counterterrorism law to criminalise a wide range of peaceful acts that bear no relation to terrorism."