U.S. Secretary of State John Kerry is ramping up his push for a proposed Gaza ceasefire, according to reports on Friday, and has called regional leaders from his station in Cairo to consider the temporary measure. 

The proposal calls for a seven-day ceasefire starting Sunday, and has been backed by the United Nations. Kerry's aides told Reuters the urgency is a result of Thursday's 15 deaths at a U.N.-run school in the northern Gaza Strip. The ceasefire would also coincide with the ending of Ramadan, the Muslim month of fasting and prayer, which would usher in a feast that would begin Sunday or Monday. 

As of Friday, Gaza officials have said the conflict has left more than 815 dead, with 27 people killed Friday, including Salah Hassanein, the head of media operations for Hamas ally Islamic Jihad, and his son.

Demonstrators have also complicated the conflict along the West Bank after the Palestinian Fatah movement called for a "day of rage." About 10,000 people marched against an Israeli army checkpoint, crafting Molotov cocktails and hurling rocks.

Israeli officials have said an army reservist was killed in Gaza on Friday, and that 33 soldiers have been lost in their ground advance, which began last Thursday.

Israeli Prime Minister Benjamin Netanyahu is expected to convene the security cabinet on Friday to discuss the potential humanitarian truce, but will not, according to an Israeli official, consider ending the tunnel mission along Gaza's eastern frontier. The truce has been floated as a possibility for several days, without an official decision.