Human Rights Watch on Sunday blasted Kuwait over a 20-month jail sentence served on a female online activist for "offending the emir" and urged the Gulf state to end such prosecutions.
The appeals court on Wednesday upheld the sentence on Sara al-Darees for making remarks on Twitter deemed insulting to the emir.
The sentence "further erodes the right to free speech in Kuwait," the New York-based rights group said in a statement.
"The Kuwait authorities over the past year have prosecuted dozens of people for peaceful political statements," said Joe Stork, acting Middle East director at HRW. "The government should tolerate this kind of criticism, not persecute people who dare express it."
At least three youth activists are serving jail terms on similar charges and many others are still on trial, including former opposition lawmakers.
"The government should drop charges against those accused or convicted of crimes solely for exercising their right to freedom of expression, and it should amend Kuwait's criminal code to remove the crime of 'offending the emir'," Stork said.
"Kuwait used to have a better reputation than most other Gulf states in respecting the right to free speech," he added. "But with each case like this, the authorities are lowering themselves to the standards of the rest of the region."
According to the verdict, Darees now has to go to jail unless the Supreme Court agrees to grant her bail until it has reviewed her challenge to the ruling.
Darees, a teacher, is the second Kuwaiti woman to be jailed on charges of insulting Emir Sheikh Sabah al-Ahmad al-Sabah on Twitter.
Last month, the lower court sentenced online activist Huda al-Ajmi to 11 years in jail for posting remarks on Twitter deemed insulting to the emir and calling for the overthrow of the regime.