CAIRO (Reuters) - Egypt's liberal coalition issued an "urgent call" for supporters to take to the streets on Friday in response to demonstrations by Islamist supporters of deposed President Mohamed Mursi.

The National Salvation Front, which endorsed the army's removal of Mursi and a plan it issued for holding new elections, said people must protect what it called the "June 30 Revolution" - referring Sunday's mass rallies that prompted the army move.

NSF spokesman Khaled Dawoud told Reuters that plans by Mursi's Muslim Brotherhood and their Islamist allies to hold protests on Friday amounted to a "counter-revolution".

The military authorities have urged people to demonstrate peacefully and have said they will keep rival factions apart.

(Reporting By Maggie Fick; Editing by Alastair Macdonald)