Updated

One of Venezuela's most high-profile politicians has called an anti-government march on Saturday, but the main opposition coalition is not endorsing the protest, underscoring fissures among critics of the country's socialist government.

In a recording leaked from his prison cell over the weekend, former Mayor Leopoldo Lopez asked people unhappy with the administration of President Nicolas Maduro to take to the streets for a massive, peaceful demonstration to demand releasing political prisoners and scheduling a legislative election.

The Harvard-educated Lopez, who represents the more radical wing of the opposition, has been jailed for 15 months in connection with a bloody street protest movement that swept Venezuela in the spring of 2014.

On Tuesday, the coalition that includes Lopez's party said it would not endorse the rally because it had been unable to reach a consensus under the circumstances. The statement suggested the difficulty of coordinating with an imprisoned leader, though even when he was free, Lopez clashed with other opposition politicians about the wisdom of big street protests.

Lopez and fellow jailed former mayor Daniel Ceballos say they launched a hunger strike last weekend to protest what they see as creeping authoritarianism. Government officials have said Lopez is still eating, but the men's families affirmed Tuesday that they really have stopped.

"Their hunger strike represents the suffering of all Venezuelans," Lopez's wife, Lilian Tintori, said.

Lopez has been kept almost mostly out of public sight since his arrest in February 2014. It's a striking contrast to the two years the late President Hugo Chavez spent in prison after a failed coup in 1992. The socialist leader regularly received guests and gave television interviews.

Despite the coalition stand, moderate opposition leader Henrique Capriles, who came close to beating Maduro in the 2013 presidential election, said Wednesday that he planned to attend.

"In support of freedom for our companions who are political prisoners, I'm going to participate without seeking to divide," he wrote on his Twitter account.