In his first telephone conversation with the new Irish prime minister, President Donald Trump told the Irish leader that he knows numerous Irish in America and he feels like he knows all of them.
The "introductory" phone call between the two took place on Tuesday.
Mr Varadkar also said he would "never shirk" from raising issues such as climate change with the USA government and its representatives in Ireland. I know so many of them, too.
Mr Varadkar's predecessor Enda Kenny invited Mr Trump to Ireland last March.
During the 15-minute conversation, Trump and Varadkar, who were speaking for the first time, also delved into topics like Brexit and climate change (let's hope he convinced Trump of its existence).
The Taoiseach also spoke to UK Prime Minister Theresa May this evening to discuss the ongoing talks aimed at restoring the power-sharing Executive in Northern Ireland.
Trump made the phone call with media present and was photographed behind his desk in the Oval Office.
The border between Northern Ireland, which is part of the United Kingdom, and the Republic of Ireland, an European Union member, will become the only land frontier between the UK and the European Union after Britain exits the bloc in March 2019.
Added the taoiseach: "I assure the deputy that in any dealings I have with the American government and in the interactions and engagement I have with the chargé d'affaires who is here and who is acting US ambassador to Ireland, I will approach them based on the long-standing friendship that exists between our countries and the familial, cultural and economic links but I will never shirk from raising issues such as climate change".