Reuters: A prominent opposition figure who has just been released from jail on a royal pardon will go on trial in Bahrain this month on new charges of urging the overthrow of the government, state news agency BNA said on Wednesday.

BNA did not name the accused man but Bahrain's Akhbar al-Khaleej and al-Wasat newspapers said it referred to Ibrahim Sharif, the former head of the secular National Democratic Action Society, or Waad.

The Advocate General said public prosecutors had referred him to the High Criminal Court on charges that also included "threats and inciting hatred against the political regime".

The trial will start on August 24.

In June, Sharif was released by a royal pardon after more than four years in prison. He had been jailed for his role in the 2011 Arab Spring uprising that called for democratic reforms in the island kingdom, a U.S. ally.

He was re-arrested three weeks later following a July 10 speech in which he had allegedly called for the overthrow of the government.

The U.S. State Department expressed concern over the re-arrests of Sharif and other opposition figures, saying they raised serious concerns about restrictions on freedom of expression.

Bahrain has experienced sporadic unrest since 2011, when its security forces, backed by Saudi troops, ended protests calling for democracy in the country, which has a Shi'ite Muslim majority but a Sunni ruling family.

The opposition says the government is attempting to stifle free speech by jailing peaceful political dissidents.

The government has accused the opposition of stirring up violent protests and of links to Shi'ite Iran, which both it and Tehran deny.

"The defendant has revealed that he is still committed to his hateful and criminal activities for which he was previously convicted," Bahrain's Public Prosecution office said in a statement, without naming the person in question.