Taoiseach Enda Kenny rounded on Independent TD Clare Daly after she accused him of showcasing Ireland "as a nation of pimps, prostituting ourselves in return for a pat on the head".
He described as a disgrace remarks about US president Barack Obama, whom she described as a "war criminal" who had increased by 200 per cent the use of drones, resulting in the deaths of thousands of people.
She said there was speculation this morning on “whether you were going to deck the Cabinet out in leprechaun hats decorated with a bit of stars and stripes to really mark abject humiliation”.
Mr Kenny retorted: "I think your comments are disgraceful. I think they do down the pride of Irish people all over the world who are more than happy to see this island being host to the G8. "
The Taoiseach said: "And for you to stand up and criticise the American president for giving a continuation of support for a fragile peace process in Northern Ireland, where over 3,000 people lost their lives in 30 years, is a disgraceful do-down."
Ms Daly, a TD for Dublin North, hit out at the “almost unprecedented slobbering” over the Obama family’s visit. “It’s really hard to know which is worst, whether it’s the outpourings of the Obamas themselves or the sycophantic falling over them by sections of the media and the political establishment,” she said.
"We've had separate and special news bulletins by the State broadcaster to tell us what Michelle Obama and her daughters had for lunch in Dublin, but very little questioning of the fact that she was having lunch with Mr Tax Exile himself," she said in reference to U2's Bono.
She described Mr Obama as a “war criminal”, having “just announced his decision to supply arms to the Syrian opposition, including the jihadists, fuelling the destabilisation of that region, continuing to undermine secularism and knock back conditions for women”.
Ms Daly said: “This is the man who is in essence stalling the Geneva peace talks by trying to broker enhanced leverage for the Syrian opposition by giving them arms - and to hell with the thousands more who’ll lose their lives, or the tens of thousands who will be displaced.
“This is the man who has facilitated a 200 per cent increase in the use of drones which have killed thousands of people, including hundreds of children.”
She asked the Taoiseach what he was going to do to ensure no weapons for Syria are going to go through Shannon, in breach of our international laws on neutrality.
“What steps are you going to take to showcase this country, not as a lapdog of US imperialism, but as an independent nation with an independent foreign policy which takes a lead in international diplomacy to outlaw the use of drones?”
Mr Kenny rounded on her for criticising the US president, “who wants to support that [peace] process visibly, personally and with assistance from the US, where 35 million Irish-Americans want this peace process to continue”.
The Taoiseach also said there was a serious discussion about Syria at the G8 summit. “Ireland took a very clear position on this as articulated by the Tánaiste - that the embargo should not be lifted.”