Israel's ambassador to Ireland should be expelled until a ceasefire between Israel and Hamas is imposed, Sinn Féin has said.
The party has changed its stance after previously stopping short of calling for the measure.
Sinn Féin had faced some criticism over its position, including from the SDLP and People Before Profit.
On Friday, party president Mary Lou McDonald said the deepening scale of the crisis means sanctions are needed.
Israel's prime minister, Benjamin Netanyahu, has said there will be no temporary ceasefire until Israeli hostages are released from Gaza.
Israel began bombing Gaza after Hamas killed more than 1,400 people in Israel and kidnapped more than 200 others on 7 October.
The Hamas-run health ministry has said more than 9,000 people have subsequently been killed in Gaza.
"Our approach has been ceasefire from the get-go and we're not outliers in that regard," Mrs McDonald said.
"That is the international law which remains our priority but as Israel turns its face away from that call for ceasefire, as the crisis deepens and the violence becomes all the more intense, clearly, there has to be a consequence here in Ireland."
"The Taoiseach (Irish prime minister) and the government, we believe, have to follow that logic now of their own assessment, which is that Israel is not acting now purely in self-defence, and they are inflicting collective punishment on an innocent civilian population."
Sinn Féin said the Israeli ambassador, Dana Erlich, should "no longer enjoy diplomatic status in Ireland" until a ceasefire is announced.
The party's youth wing had already called for the ambassador to be expelled last month, after an attack at a hospital in Gaza.
'Isn't just self-defence'
Last week, the Irish government said there were no plans to expel the ambassador with Taoiseach (Irish PM) Leo Varadkar saying it was important to have "some line of communications open".
Speaking to reporters on a trip to South Korea on Friday, Mr Varadkar said what is happening in Gaza is not just self-defence on the part of Israel, but it "resembles something more approaching revenge".
His comments come as Israeli ground troops began encircling Gaza City on Friday morning.
He said it is very important that people "never forget where this started", adding this phase of the conflict started with a Hamas attack on Israel where 1,400 civilians were killed.
"I strongly believe, like any state, Israel has a right to defend itself, has the right to go after Hamas, so they cannot do this again," Mr Varadkar said.
"But what I am seeing unfolding at the moment isn't just self-defence, it resembles something more approaching revenge and that's not where we should be and I don't think it is how Israel will guarantee its future freedom and security."
Ms Erlich herself was criticised last month, after making comments about Ireland's President Michael D Higgins.
She had also questioned Ireland's neutrality, telling the Sunday Independent newspaper there was "a strong feeling in Israel that there is an unconscious bias against Israel in Ireland".