DAMASCUS, Syria (AP) – Hamas declared a cease-fire with Israel in Gaza in the name of all Palestinian factions on Sunday, in a televised announcement by its Damascus-based deputy leader.

Moussa Abu Marzouk said on Syrian television that the cease-fire will last a week to give Israel time to withdraw and open all the border crossings to allow humanitarian aid into the embattled seaside territory.

The announcement came about 12 hours after Israel announced its own cease-fire and not long after U.N. Secretary-General Ban Ki-moon urged Syrian President Bashar Assad to help make a cease-fire successful.

“We the Palestinian resistance factions declare a cease fire from our side in Gaza and we confirm our stance that the enemy’s troops must withdraw from Gaza within a week,” Abu Marzouk said.

The cease-fire comes after 22 days of fighting that killed some 1,200 Palestinians, about half of them civilians, according to Palestinian and U.N. officials. Thirteen Israelis also died.

After the Israeli cease-fire went into effect, militants in Hamas-ruled Gaza fired salvos of rockets into southern Israel.

Israel had announced it would not pull its troops from Gaza until rocket fire halts, and the Islamic militant Hamas vowed to fight on as long as Israeli soldiers remained.