Spanish police, working with their French colleagues, arrested Tanem on Wednesday on suspicion of “terrorist activity” in Almeria, southern Spain.
He is suspected of fighting against President Bashar al-Assad’s regime and helping would-be jihadis to cross the border between Turkey and Syria.
He denies the charges.
Tanem will be handed over to France, where his is wanted for allegedly sending for people to join the ranks of Islamic State of Iraq and the Levant (Isis) and the Al-Nusra Front in Syria, in the next few days, officials say.
Hundreds of people suspected of plotting Islamist violence have been detained in Spain in the 10 years since the Madrid train-bombings that killed 191 people.