CAIRO, Nov 14 (Reuters)- Arab foreign ministers will meet on Saturday at the Cairo-based Arab League to discuss the Israeli attack on Gaza, Deputy Arab League chief Ahmed Ben Helli told Reuters.

"The Arab League called on Arab foreign ministers to hold a meeting in Cairo this Saturday to investigate the Israeli assault on Gaza Strip," Ben Helli said on Wednesday. His comments were also carried by Egypt's news agency MENA.

Israel launched a major offensive against Palestinian militants in Gaza on Wednesday, killing the military commander of Hamas in an air strike and threatening an invasion of the enclave that the Islamist group vowed would "open the gates of hell".

The senior League official handling Palestinian affairs, Mohammed Sobeih urged the Arab ministers to come up with strong decisions from their upcoming meeting.

"We (Palestinians) urge the Arab states to have a clear and strong stand that would press the world to force Israel to stop its attack," Sobeih told Reuters.

The Palestinian Authority urged the U.N. Security Council to take a stand on Israel's offensive in the Gaza Strip, which it said constituted "illegal criminal actions".

Palestinian President Mahmoud Abbas and Egypt's Islamist President Mohamed Mursi both had called for an emergency Arab meeting over the Israeli strikes.

Mursi, who repeatedly has pledged to honour the 1979 peace agreement with Israel, condemned the raids as a threat to regional security and withdrew his ambassador from Israel. He also summoned the Israeli envoy to Cairo to deliver a protest and called for an emergency meeting of the Security Council.

Mursi who hails from Egypt's popular Muslim Brotherhood group, has since his election last June strengthened the relationship between Egypt and Hamas, the political front of the Palestinian Muslim Brotherhood.

The political wing of Egypt's Brotherhood, the Freedom and Justice Party, issued a strong condemnation statement of the Israeli attack.