Bahrain Mirror (Reuters): A prominent Bahraini opposition figure was sentenced to a year in jail on Wednesday on charges of insulting the kingdom's ruling system in a speech last year, his defence lawyer said.

But the court cleared Ibrahim Sharif, former head of the secular National Democratic Action Society, or Waad, of the more serious charge of calling for regime change through illegal means, the lawyer, Mohammed Ahmed, told Reuters by telephone.

The public prosecution, in a statement on social media that did not refer to Sahrif by name, said a suspect was convicted of "insulting the constitutional system in the country and mocking it" but cleared him of calling for regime change in violation of the constitution.

"The prosecution is currently studying the reasons for the ruling to acquit the suspect of some charges and to look into the possibility of appealing it if legal basis were found for that," the prosecution said.

Sharif was freed in June last year by royal pardon after serving more than four years in jail for his role in an uprising demanding political reforms in the Gulf Arab island nation. He was Waad leader at the time of his arrest in March 2011.

Bahrain, which hosts the U.S. Fifth Fleet, has experienced sporadic unrest since mass protests in 2011 led by majority Shi'ite Muslims demanding reforms and a bigger role in the Sunni-led government. That uprising was put down with military help from neighbouring Sunni power Saudi Arabia.

Bahrain says the opposition has a sectarian agenda and is backed by Shi'ite power Iran. Shi'ite groups deny those charges and Waad says it is secular.

In a speech to Muslim scholars, newspaper editors and members of the Shura council this week, Interior Minister Shaikh Rashid bin Abdullah al-Khalifa announced a series of measures to curb what he described as the expansion of Iranian-inspired militancy in Bahrain.

Those included setting up a committee to monitor financial transaction of individuals and organisations, restricting citizens aged between 14 and 18 from conflict zones and protecting places of worship "from religious and political extremism and incitement".