Taoiseach Micheál Martin has strongly condemned Israeli airstrikes on Gaza, which he described as the collective punishment of Palestinians.
Speaking in Brussels ahead of an EU summit, he said Europe needed to put as much pressure on Israel as possible to stop the bombing.
It comes as hundreds of people have been killed in Gaza since the Israeli military resumed airstrikes on Monday night, according to Gaza health authorities.
"There was no warning. Many, many people came back after the ceasefire to their homes in the expectation that they were going to experience some degree of peace and harmony," Mr Martin said.
"And that has been shattered by what appears to be very indiscriminate bombing, just indiscriminate bombing."
He accused Israel's defence minister Israel Katz of statements which amounted to the collective punishment of the Palestinian people in Gaza.
"It is quite shocking, it needs to stop and Europe needs to say stop to the killing and slaughter.
"We do also need a release of all hostages, and we need to move very quickly to phase two of the ceasefire, which was originally agreed and what should be complied with."
Ireland doing more than 'sweet words'
Tánaiste Simon Harris and Independent TD Catherine Connolly have clashed in the Dáil over claims that the Government is failing to adequately condemn the war in Gaza and "genocide in our name".
Deputy Connolly repeatedly referred to the "genocide" in Gaza and what she said was the "total disregard of Netanyahu of international law", a situation she said was being highlighted to TDs in "thousands" of emails.
She said the "horror in Palestine in the last few days" and "invasion by air and by land" is about Israel coming "back to finish the job".
She said that "apart from our sweet words", Ireland has been "actively colluding with genocide" by not ending military flights through Shannon or enacting the Occupied Territories Bill to date.
The Tánaiste responded to the claims by saying he is "sick and tired of you demeaning my position" and that Ireland is doing more than simply saying "sweet words".
He said Ireland has been "actively involved in the International Court of Justice" case on the matter and has paid for trucks in Jordan with enough aid for 6,000 people.
He said Ireland has also spent €38 million to continue supporting UNWRA "when other people have walked off the pitch", is working with Arab countries to find a solution, and is "engaging" with plans to advance the Occupied Territories Bill.
He took issue a second time with Deputy Connolly's "sweet words" remark, telling her "not to be so flippant".
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Deputy Connolly responded by initially saying she would "prefer to stay silent" in protest at the remarks, before saying a number of times that in her view the Government is "committing genocide in our name".
She said Israel should be publicly condemned in the same way as Russia was for its invasion of Ukraine, and that Ireland should stop the US from "using Shannon to carry destructive weapons".
The Occupied Territories Bill must be enacted "immediately", she added.
Mr Harris said he and the Taoiseach are meeting with Jewish groups, adding that anti-semitism is disgraceful and should be condemned.
He said he utterly condemns the actions of Hamas, including "parading child caskets", and told Deputy Connolly to "read our [the Irish Government's] submission to the International Court of Justice" if she wanted to see what the Government's view is on the question of genocide in Gaza.
He concluded by telling Deputy Connolly that "it must be exhausting to think that you care, alone".
