The ongoing humanitarian crisis in Gaza and the war in Ukraine were among the issues Taoiseach Simon Harris and US president Joe Biden discussed in a call on Monday night.
In Mr Harris' first phone call with the US president, they also discussed powersharing in Northern Ireland, the institutions of the Good Friday Agreement and the ongoing work of the US special envoy to Northern Ireland for economic affairs, Joe Kennedy.
Mr Kennedy, the grandson of former US attorney general and presidential candidate Bobby Kennedy, was appointed to the newly created diplomatic role by Mr Biden.
Mr Harris and Mr Biden also discussed the humanitarian catastrophe in Gaza, "the need for an immediate ceasefire, for all hostages to be released and for aid to flow freely".
The Taoiseach also briefed president Biden on the Ukraine Peace Summit held in Switzerland over the weekend and his conversation there with US vice president Kamala Harris.
President Biden told the Taoiseach that the United States would continue to support Ukraine "and that the world must stand with Ukraine for as long as it takes".
The pair also discussed the "deep and growing" economic ties between Ireland and the United States.