Graeme McDowell will host the Dubai Duty Free Irish Open for the next two years, starting with the 2020 event at Mount Juliet.
He will also host the 2021 edition, the venue for which is yet to be confirmed, although it has been reported that Portstewart told members at an AGM that an agreement has been reached for the tournament to return there.
"I would love to bring the event to Northern Ireland in 2021," said McDowell. "But my focus now is on next year at Mount Juliet Estate and making sure that is another world-class sporting occasion."
McDowell succeeds Rory McIlroy, who hosted from 2015 to 2018, and Paul McGinley, who was tournament host at Lahinch this year.
Very excited to build on this momentum in Irish golf https://t.co/5r1HxyPWNU— Graeme McDowell (@Graeme_McDowell) December 2, 2019
McDowell said it'll a "huge privilege" to host the event, which takes place at Mount Juliet from May 28-31, 2020.
"The event has gone from strength to strength over the last few years with the support of Dubai Duty Free and the efforts of Rory and Paul as hosts, alongside everybody at the European Tour.
"I’m really looking forward to taking on that responsibility over the next two years and adding to the history of this great tournament, which has become a global spectacle that Irish golf fans can be proud of."
The 40-year-old major champion and Ryder Cup star had his best finish at his national open in 2014, finishing sixth at Fota Island.
"His vast experience and talent will no doubt further grow the interest among both players and fans," said Dubai Duty Free CEO Colm McLoughlin.
"Mount Juliet will be a magnificent venue for 2020, it is a stunning parkland course, and is often referred to as a ‘great spectator course’ by fans.
"We are looking forward to working with Graeme and the European Tour over the coming months and wish him the best of luck in his work."
McDowell previously competed at Mount Juliet during the 2004 American Express Championship, which was won by Ernie Els.
"We are delighted with the announcement that Graeme McDowell will be our host here at Mount Juliet Estate next year and it will be a pleasure to welcome Graeme back," said Damien Gaffney, director of Tetrarch, who owns Mount Juliet.
"To have a Major Champion such as Graeme hosting this wonderful event is an honour for all of us."
Keith Pelley, European Tour chief executive, added: "He's a terrific ambassador for our game, and I'm certain he will enjoy the role of host and be a great success in it, building on the work of Rory and Paul.
"Having Graeme as host for the next two years allows us to plan and maximise the many opportunities that exist across the island of Ireland for both editions."