CAIRO, July 24 (Reuters) - Egypt's second biggest Islamist Party said on Wednesday it rejected a call by the head of the army for mass rallies to give him a mandate to confront violence unleashed after the military deposed the country's Islamist president.

"The state does not need a mandate to perform its duty as long as it is within the boundaries of the law," the party, Nour, said in a statement. "Violations of the law should be handled by the state, but the state's violations of the law threaten the very existence of the state," it said.

(Reporting by Ali Abdelatti and Yasmine Saleh; Writing by Asma Alsharif; Editing by Matt Robinson)