Tánaiste and Minister for Foreign Affairs Micheál Martin has condemned Israel for the "brutal expansion" of military operations in Gaza. 

Martin issued a statement after an Israeli air attack on a school housing displaced Palestinians in the city of Khan Younis killed at least 30 people. 

The attack, the fourth such attack in as many days, also wounded at least 53 people, while most of the victims were women and children. 

"Despite ceasefire proposals on the table and ongoing negotiations, we have watched this past week a brutal expansion of Israeli military operations in Gaza that has resulted in the deaths of dozens of innocent civilians and the destruction of healthcare, education, and humanitarian facilities," Martin said in a statement on Friday. 

"This includes an airstrike on a school in Khan Younis where hundreds of displaced Palestinians had sought shelter." 

Martin noted that it has been reported while people had gathered to watch a children's soccer match, describing it as "a particularly grim detail in a week where millions across Europe have watched football from the safety of their living rooms".

"Attacks on humanitarian facilities and locations where civilians are sheltering are abhorrent and are clear violations of international humanitarian law.

"We must have accountability for all civilian deaths and violations of international humanitarian law by all actors in this conflict." 

He called for all hostages to be released and for unconditional access for independent international investigative mechanisms and bodies. 

Martin additionally called on both Israel and Hamas to "immediately" implement the three-phase ceasefire proposal endorsed by the United Nations. 

The first stage of the proposal calls for a six-week ceasefire and the release of Israeli and Palestinian hostages. It also calls on Israel to allow "sufficient" humanitarian aid to enter Gaza. 

"We urge Israel and Hamas to implement immediately the three-phase ceasefire proposal endorsed by the UN Security Council. The bloodshed, destruction, and trauma must end," Martin said.