More than a dozen political parties and unions have thrown their support behind widening street protests against Algerian President Abdelaziz Bouteflika and denounced the government's "stubborn" hold on power.

More protests are planned for Friday challenging Bouteflika's fitness to run for a fifth term. The Algerian leader has been in power since 1999 but has been all but absent from the public eye since a stroke in 2013. He has been hospitalized in Switzerland since last month for what the government describes as medical tests.

At a meeting that ended late Thursday, 15 opposition parties and four unions praised the protest movement and criticized the government for its "stubborn power" in insisting upon the elections in April. Protesters are calling for a general strike if the government doesn't back down.