The call comes as the POTUS has been given the green light to introduce his travel ban.
The Taoiseach said numerous illegal Irish in the United States had originally travelled on legitimate documentation but for a variety of reasons now needed to regularise their situation.
The ban has been reinstated until autumn. "That was a great victory that you had", Trump said.
The President asked for an update on the Northern Ireland peace process and the situation regarding border controls between the North and the Republic.
President Trump speaking with Taoiseach Leo Varadkar today.
Trump congratulated Varadkar on his "great victory" and said he feels like he knows all the Irish people in America. During the call, reporters from the Irish media were present.
The call took place at 11.15 a.m.in Washington, 4.15 p.m.in Dublin.
President Donald Trump had his first telephone conversation with Ireland's new prime minister, Leo Varadkar.
The 38-year-old Varadkar is Ireland's youngest prime minister.
"I will not, of course, rescind that invitation".
The call lasted just under 15 minutes with topics ranging from climate change to Brexit. As of yet, however, there has been no transatlantic discussion on such a presidential visit and there was no talk about such a visit during Tuesday's phone exchange.