Veteran broadcaster Mike Murphy has launched a scathing attack on Donald Trump, calling him a "narcissist" and "appalling creature" for withholding funds from the World Health Organisation (WHO).
Former Labour Party leader Brendan Howlin added his criticisms, branding the US president an "ignoramus" and declaring his presidency in the current crisis a "tragedy".
The two were taking part in a web conference hosted by the African-European Parliamentarians Initiative on responding to Covid-19 in Africa.
Mr Murphy, who chaired the event, asked an expert panel why there had not been more uproar over Mr Trump's decision to withhold the US's annual $400m (€368m) contribution to the WHO.
Mr Trump has claimed the WHO mismanaged the spread of Covid-19 - claims the organisation has strongly refuted.
"Why did world leaders not scream in protest?" Mr Murphy asked, saying he did not understand why they had not tackled the "narcissist" or called up to tell the "appalling creature" to change his "pathetic" behaviour.
"He is using his nightly briefings as an electioneering ploy," he said.
"It's all 'elect me - I'm doing a great job'."
Mr Howlin agreed that Mr Trump's response was divisive.
"It is a tragedy for the world that the US is led by an ignoramus at this time of real need. Everything he does is damaging to the solidarity that is needed," he said.
The event was addressed and watched by parliamentarians, public health experts and community leaders in Ireland, the UK and Africa.
President Michael D Higgins sent a video message, strongly urging debt cancellation for African countries.
He said it was almost impossible to ask them to adopt the hygiene and social distancing measures relied upon in Ireland when so many places lacked clean water and suffered extreme overcrowding, and where there were no social supports for those who did not go out to work.
"It would be an invitation to starve," Mr Higgins said of trying to impose a stay indoors policy.
"Europe has a legacy in Africa that it would like to forget but which Africans have not forgotten.
"Now is an opportunity to make a new beginning and not only respond to Covid-19 but to the structural imbalances that are there - unfair trade and the burden of debt."