Bahrain has charged jailed Shiite opposition leader Sheikh Ali Salman with "spying" for Qatar, state prosecutors said Wednesday, after allegations he whipped up protests at Doha's request.

The investigation into purported links between Salman and Qatar was first launched in August, after a quartet of Arab countries -- Bahrain included -- accused their gas-rich neighbour of supporting terrorism and close relations with Shiite Iran.

State-run Bahrain Television aired a report which claimed that neighbouring Qatar was behind anti-government protests that have shaken the tiny kingdom for the past six years.

It alleged that Qatar's former premier Sheikh Hamad bin Jassem Al-Thani contacted Salman -- then head of Bahrain's largest opposition group, Al-Wefaq -- in 2011 and asked him to urge protesters to flood the streets and ramp up pressure on the state.

Salman has been behind bars since 2014 serving a nine-year sentence for allegedly inciting hatred.

He has now been charged with "spying on behalf of a foreign country ... with the aim of carrying out subversive acts against Bahrain and harming its national interests," the Bahraini prosecutor's office said in a statement.

The dissident was also charged with "revealing defence secrets to a foreign country and disseminating information that would harm Bahrain's status and reputation".

The statement did not say when the trial would begin.

Al-Wefaq was the largest group in parliament before its lawmakers resigned en masse in protest at the crushing of Arab Spring-inspired demonstrations in 2011 calling for an elected government.

The Shiite Muslim movement has called for Sunni-ruled Bahrain to become a constitutional monarchy.

The Shiite majority in Bahrain, which has been ruled by the Al-Khalifa dynasty for more than two centuries, has long complained of marginalisation and the country has been rocked by sporadic unrest since 2011.

Source: AFP