In a telephone conversation on Tuesday, Sheikh Salman said that he had devoted his life to serving Bahrain.
“I never practiced in anything that would harm this country,” he added.
The opposition leader was jailed in December 2014 for allegedly inciting hatred against the regime.
The new charges against him stem from a taped telephone conversation between Salman and Qatar’s former prime minister.
According to Manama’s prosecutors, the conversation is proof of Doha’s role in Bahrain’s popular uprising.
But the allegations have been widely discredited by the sheer fact that the recorded conversation – aired on Bahrain’s state-run TV in August – was part of a 2011 Saudi-US initiative aimed at resolving Bahrain’s political crisis.
Qatar played the role of a mediator within the framework of the initiative, which was backed by the Bahraini monarch.