WASHINGTON - US President Barack Obama reiterated Friday his country's support for Israel's right to defend itself against rocket attacks from militants in Gaza Strip, the White House said.

Obama expressed his support during a phone conversation with Israeli Prime Minister Benjamin Netanyahu, who called the US president to "provide an update on the situation in Israel and Gaza," the White House spokesman's office said in a statement.

Netanyahu "expressed his deep appreciation to the president and the American people for the US investment in the Iron Dome rocket and mortar defense system, which has effectively defeated hundreds of incoming rockets from Gaza and saved countless Israeli lives," it added.

Obama also expressed regret over the loss of Israeli and Palestinian civilian lives as he discussed with Netanyahu "options for de-escalating the situation," the statement said, providing no further details.

Also on Friday, Obama called his Egyptian counterpart Mohammed Morsi to praise the latter's efforts to ease the tensions between Israel and the Palestinians, the White House said.

This was the second time that Obama has talked with Netanyahu and Morsi since Wednesday, when he spoke by phone separately with both leaders about the escalating violence in Gaza.

Obama supported the Israeli right to defend itself from attacks, while urging Netanyahu to do everything possible to avoid civilian casualties.

The recent conflict between Israel and Islamic Hamas movement in the Gaza Strip broke out after Israeli war jets assassinated on Wednesday Hamas armed wing General Command Ahmed al-Jaa'bari and his bodyguard in a targeted airstrike.

Since then, Hamas armed wing al-Qassam Brigades and other minor militant groups have fired 550 rockets into Israel, killing four Israelis and wounding more than 10 others. Israel has answered with massive air strikes on Gaza Strip, which have so far killed 24 Palestinians, mostly civilians, and wounded 270 others.

Israel on Friday intensified its air strikes on Gaza, as a rocket fired by Palestinian militants landed near Jerusalem for the first time. On Thursday, two long-range rockets were fired toward Tel Aviv, setting off sirens in the city for the first time since the 1991 Gulf War.

The Israeli cabinet on Friday evening okayed the military's request to expand the enlistment of reserve troops to 75,000, fueling speculation that a ground offensive against the Hamas-controlled Gaza Strip is imminent.