Famine has been declared twice in the past 13 years: in Somalia in 2011 and in parts of South Sudan in 2017
Mosques will be authorised to open 20 minutes before Friday prayers and should close 20 minutes after they finish, state TV said on Twitter, citing the ministry of Islamic affairs.
Saudi authorities said on Monday that restrictions would be lifted in three phases, culminating in a curfew ending - with the exception of the holy city of Mecca - from June 21.
The hajj and umrah pilgrimages, which attract millions of travellers from around the world, will remain suspended until further notice.