Human Rights Watch on Sunday urged the European Union foreign policy chief Catherine Ashton to condemn a Saudi court decision sentencing seven cyber activists to up to 10 years in jail.
HRW's call came ahead of Sunday's meeting in Manama where Ashton is chairing a joint EU-Gulf Cooperation Council on how to boost cooperation between the two bodies.
"Sending people off to years in prison for peaceful Facebook posts sends a strong message that there's no safe way to speak out in Saudi Arabia, even on online social networks," said Joe Stork, HRW's deputy Mideast director, in a statement.
"If the EU doesn't raise these cases with Saudi officials this weekend, its silence will look like craven compliance with the rights abuses of an authoritarian state."
A specialised Saudi criminal court on June 24 sentenced the seven "government critics" for "allegedly inciting protests and harming public order, largely by using Facebook," said the New York-based watchdog.
The court also barred them from travelling for additional periods.
The men were arrested in September 2011. Their trial began on April 29.
"Authorities did not accuse the seven of directly participating in protests, and the court failed to investigate their allegations that intelligence officers tortured them into signing confessions," HRW added.
They were all convicted of joining Facebook pages to "incite protests, illegal gathering, and breaking allegiance with the king," the rights group said.
Oil-rich Saudi Arabia's Shiite-populated Eastern Province has been rocked by sporadic violence since 2011.
Residents have clashed with police to protest what they say is the marginalisation of Shiites in Sunni-ruled Saudi Arabia.
There are an estimated two million Shiites in the kingdom of around 27.5 million people.
It is unclear if the seven defendants are Shiite.