Palestinian President Mahmud Abbas held talks with exiled Hamas leader Khaled Meshaal on Thursday as renewed fighting raged in Gaza following the collapse of Egyptian-brokered truce efforts.

The talks in Doha, where Meshaal is based, were hosted by Qatari Emir Sheikh Tamim bin Hamad al-Thani, a key backer of the Islamist movement which dominates Gaza, the Gulf state's QNA news agency reported.

Israeli warplanes killed three top Hamas commanders in southern Gaza on Thursday, inflicting a heavy blow on the movement's armed wing after failing to kill its top military chief.

As the six-week war between Israel and Hamas raged on, leaving Egyptian mediated truce talks in tatters, warplanes pounded Gaza killing three members of the Islamist movement's armed wing, the Ezzedine al-Qassam Brigades.

Thirty-one Palestinians have been killed and at least 120 wounded by Israeli strikes across Gaza since the collapse of a temporary truce, the emergency services said Wednesday.

And the armed wing of Hamas warned foreign airlines against flying into Tel Aviv, threatening to step up its six-week conflict with Israel and declaring truce talks in Cairo over.

Arab League chief Nabil al-Arabi accused Israel on Wednesday of "blocking" all attempts to end the Gaza conflict, a day after the collapse of a ceasefire in the Palestinian territory.

"Israel is blocking any kind of agreement leading to calm" in the Gaza Strip, Arabi told journalists.

The United States blamed rocket fire from Gaza for a breakdown in indirect talks between Israel and Palestinian authorities on a durable ceasefire Tuesday, and said Hamas bore responsibility.

"Hamas has security responsibility for Gaza... Rocket fire came from Gaza," State Department spokeswoman Marie Harf said, blaming the Palestinian Islamist group for renewed fighting.

Israel and Palestinian militants resumed fire across the Gaza border on Tuesday, sparking panic across the war-torn enclave and halting truce talks.

Gaza emergency services said that a woman and a child were killed and 16 people injured in one strike in Gaza City.

Israeli and Palestinian negotiators in Cairo faced a new midnight deadline Tuesday to end the bloodshed in Gaza after agreeing overnight to extend an existing truce by 24 hours.

News of the last-minute extension was confirmed by both sides shortly before a five-day ceasefire was to expire at midnight local time (2100 GMT Monday).

The United Nations is ready to check imports of construction material sent to Gaza in order to ease Israel's concerns that supplies could be used to rebuild Hamas tunnels, a U.N. envoy said Monday.

U.N. Mideast envoy Robert Serry told the U.N. Security Council that reconstruction of Gaza remained the main priority once a durable ceasefire is agreed between Hamas and Israel.

Negotiators in Cairo were pushing Israel and the Palestinians to put a decisive end to weeks of bloodshed in Gaza Monday as the clock ticked down on another temporary truce.

As the death toll in the war-torn Gaza Strip pushed over 2,000, Egyptian negotiators were pressing both sides to reach agreement before a midnight (2100 GMT) deadline which will mark the end of a five-day truce.

Prime Minister Benjamin Netanyahu warned Monday that Israel will hit back hard if Palestinian rocket attacks from Gaza resume, speaking just hours before the midnight expiry of a five-day ceasefire.

"We are ready for all scenarios... the army is ready to respond with force if the firing (of rockets) resumes," he said in a meeting with Defense Minister Moshe Yaalon in Ashdod, a statement said.