Qatar's ruler hit out at "shameful" international inaction over the Israel-Hamas war in Gaza as he opened a Gulf Cooperation Council meeting in Doha on Tuesday.

"It is shameful for the international community to allow this heinous crime to continue for nearly two months, during which the systematic and deliberate killing of innocent civilians continues, including women and children," Sheikh Tamim bin Hamad Al-Thani said.

Israel declared war on Hamas after the militant group killed 1,200 people and took 240 hostages, according to Israeli figures, in an unprecedented attack on October 7.

The Israeli offensive has killed nearly 15,900 people in Gaza, according to the Hamas-run health ministry, around 70 percent of them women and children.

Qatar was a key mediator in negotiations that resulted in a seven-day truce, which saw scores of Israeli hostages exchanged for Palestinians prisoners and humanitarian aid, until it ended on Friday.

Qatar's ruler said his country was "constantly working to renew" the truce, but added this was "not an alternative to a permanent ceasefire".

He called for "an international investigation into the massacres committed by Israel" and for the Security Council "to assume its legal responsibility and act to end this barbaric war, and compel Israel to return to credible negotiations to achieve a just solution to the Palestinian issue".

- 'Blatant aggression' -

In a joint statement, the GCC expressed "deep concern" with what it called "blatant Israeli aggression" in Gaza.

The council praised the efforts of Qatar, Egypt and the United States in negotiating the humanitarian pause, urging a fresh truce "immediately" to "achieve a complete and sustainable ceasefire".

Turkish President Recep Tayyip Erdogan attended the session and accused Israel of "war crimes" and "crimes against humanity in Gaza", which he said "should not be left unanswered".

Both Turkey and Qatar have been vocal supporters of the Palestinian cause and have opened channels of communication with Hamas.

The wealthy Gulf state has defended the presence of Hamas, established with Washington's blessing, as a channel for conflict-resolution.