Spanish Prime Minister Pedro Sanchez on Tuesday refused to testify against his wife, who is under investigation for influence peddling, to a judge who went to question him as a witness.

The hearing, which took place at an office at the Moncloa palace, lasted "approximately 20 minutes," Marta Castro, a lawyer for far-right party Vox who was present told reporters, adding that Sanchez had Tuesday invoked his right not to testify.

Under Spanish law, one can refuse to answer questions in a case affecting close family members including spouses.