Political suppression in Bahrain a 'grave concern', Amnesty says

"Over the past two years, the crackdown in Bahrain has seen the political opposition detained, intimidated and silenced," said Devin Kenney, the rights group's Bahrain researcher, in a statement.

"We call on the authorities to stop this ongoing and escalating repression and to allow free expression of dissenting voices, including those who oppose the monarchy.

"Bahrain's international partners and allies cannot remain silent, and must use their influence to pressure the Bahraini authorities to adhere to the international standards they have committed to," Kenney said.

The Sunni-ruled Gulf island nation has been hit by waves of unrest since 2011, when security forces crushed Shiite-led protests demanding a constitutional monarchy and an elected prime minister.

Opposition movements have been outlawed and hundreds of dissidents have been imprisoned - with many stripped of their nationality.

Bahrain's two main opposition groups - the Shiite Al-Wefaq and secular Waad - are prohibited from submitting parliamentary candidates.  

Sheikh Ali Salman, who headed the Al-Wefaq group, was sentenced to life in prison on 4 November for spying for rival Gulf state Qatar, in a ruling rights groups have called a travesty.

Bahraini authorities accuse Shiite Iran of provoking unrest in the kingdom. Tehran denies the allegation.

Human rights groups have frequently said cases against activists in Bahrain - men and women, religious and secular - fail to meet the basic standards of fair trials.

Last year, Bahrain ratified a constitutional amendment granting military courts the authority to try civilians charged with "terrorism", a term that is loosely defined by the Bahraini penal code.

In June, the kingdom amended its law on political rights, prohibiting "leaders and members of political associations dissolved for violating the kingdom's constitution or its laws" from running in legislative elections.

The Gulf island-state remains a vital link for Western militaries. It is the home of the US Navy's Fifth Fleet, which patrols the oil-rich region, as well as a permanent British base.

The Trump administration lifted restrictions on arms sales to Bahrain that former president Barack Obama imposed on human rights grounds.

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