GAZA / CAIRO / TEHERAN - Salah al-Bardawil, a senior Hamas leader and member of its political bureau, was killed Sunday along with his wife in an Israeli airstrike that targeted his tent inside a camp for displaced persons west of Khan Younis, in the southern Gaza Strip.

Hamas sources said the bombing targeted a gathering of displaced people, resulting in a number of casualties. The sources considered the targeting of al-Bardawil a new escalation in Israeli attacks on the movement's leaders as well as civilians in the Gaza Strip.

Hamas mourned al-Bardawil, saying that he was a prominent political figure who had served as a member of the Palestinian Legislative Council for the Change and Reform Bloc and as one of the movement's official spokespersons.

The Israeli army has not commented on this incident yet.

The killing comes amid growing international calls to de-escalate the situation and protect civilians from the repercussions of the conflict.

Israel has proposed a two-phase plan to the Hamas movement, through Egyptian mediators, for the release of hostages held in Gaza, well-informed Egyptian sources told Xinhua on Saturday.

The initial phase of the proposal involves Hamas releasing 11 living hostages and the bodies of 16 deceased individuals. This would be followed by a 40-day truce.

Subsequently, in the second phase, Israel's proposal calls for Hamas to release all the remaining hostages in a single batch.

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The United States backs Israel's proposal, which leverages "the current military pressure," according to the sources.

Israel resumed strikes in Gaza on Tuesday, effectively ending a ceasefire with Hamas brokered by Egypt, Qatar, and the United States that began on Jan 19. Israeli forces subsequently launched ground operations across southern, northern, and central Gaza. In response, Hamas made several rocket launches targeting Israeli territory, most of which Israel said have been intercepted. 

Also on Saturday, Iran's Foreign Minister Seyed Abbas Araghchi exchanged views with his Saudi Arabian and Egyptian counterparts on Israel's renewed attacks on Gaza.

In a phone conversation with Saudi Foreign Minister Faisal bin Farhan Al Saud, Araghchi strongly condemned Israel's attacks in Gaza, and urged other countries in the region to take collective action, said the Iranian Foreign Ministry in a statement.

For his part, Faisal reaffirmed Saudi Arabia's condemnation of Israeli aggressions and emphasized regional coordination to prevent further escalation.

READ MORE: Israel threatens to annex Gaza territories if hostages not freed

In a separate phone call with Egyptian Foreign Minister Badr Abdelatty, Araghchi condemned Israel's renewed attacks on Gaza as well as obstruction of humanitarian aid delivery to the Palestinian coastal enclave "in flagrant violation" of the ceasefire agreement with Hamas.

The Egyptian foreign minister underscored the need for consultations and diplomatic efforts to prevent further escalation.

Both Egyptian and Iranian ministers agreed to maintain consultations on regional developments.