His departure sets the stage for President Trump to nominate a second Supreme Court justice after successfully nominating Justice Neil Gorsuch to the bench a year ago.
In the letter, he told Mr. Trump that effective July 31, he would end "regular active status as an Associate Justice of the Supreme Court, while continuing to serve in a senior status".
But a dissenting liberal justice said the court was making a historic mistake by refusing to recognize the ban discriminates against Muslims.
He joined his fellow conservatives in the 2000 ruling that effectively gave the US presidency to Republican George W. Bush, rather than Democrat Al Gore, by preventing any more vote recounts in Florida.
Trump's first high court nominee, Justice Neil Gorsuch, was confirmed in April 2017. We want to keep our journalism open and accessible and be able to keep providing you with news and analyses from the frontlines of Israel, the Middle East and the Jewish World.
U.S. Supreme Court Associate Justice Anthony Kennedy arrives for the funeral of fellow justice Antonin Scalia at the Basilica of the National Shrine of the Immaculate Conception in Washington, February 20, 2016.
Trump, speaking to reporters Wednesday, called Kennedy a "great justice", adding that he displayed "tremendous vision and heart".
Egyptian Commentator Dies After Watching His Country Lose to Saudi Arabia
Saudi Arabia's Salem Aldawsari flips to celebrate scoring his side's winning goal with the final kick of the game against Egypt . Football star Mo Salah scored first within the first 25 minutes, marking Egypt's fourth ever goal at the World Cup .
Utah’s Rudy Gobert wins NBA Defensive Player of the Year
Harden is the third player in Rockets history to win the award, and he is the first since Hakeem Olajuwon won in 1994. Dwane Casey was chosen Coach of the Year for his work with the Toronto Raptors, who fired him last month.
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Wojnarowski followed that up by noting the Los Angeles native wants to play in his hometown, preferably for the Lakers. If he's serious about his employment with the team, swinging a deal for Leonard would make him a man of his word.
Kennedy disappointed conservatives by joining Supreme Court decisions that affirmed the Roe decision, including a landmark 1992 ruling in the case Planned Parenthood v. Casey.
The travel ban has been fully in place since December, when the justices stopped lower court decisions that had blocked part of it from being enforced.
Kennedy visited the White House in-person before his retirement went public.
Larsen is a former law professor and special counsel to the dean at the University of MI who also clerked for the late Supreme Court Justice Antonin Scalia.
Several former law clerks have said that Kennedy, a nominee of President Ronald Reagan, preferred to be replaced by a Republican.
Gorsuch was nominated by Trump after Republicans in the Senate refused to grant a hearing to federal appeals Judge Merrick Garland, who was appointed by Barack Obama with more than 10 months remaining in Obama's term.
Kennedy, mild-mannered and professorial, followed a thoughtful, middle-of-the-road approach and often posed probing, intellectual questions of lawyers arguing cases.
Do you think there's any chance Kennedy elicited some support from conservative colleagues to preserve his history-making rulings on gay rights when he's gone?