US Supreme Court Justice Anthony Kennedy has announced he is retiring at the age of 81. Although not the oldest, he is the most senior member of the court, having been nominated by former President Ronald Reagan.

"It has been the greatest honor and privilege to serve our nation in the federal judiciary for 43 years, 30 of those years on the Supreme Court," Kennedy said. He added that his decision was motivated by the desire to spend more time with his family.

Trump's conservative pick

Since joining the nine-member court in 1988, Kennedy has been considered the swing vote between left-leaning and conservative justices. He often sided with the left-leaning justices on social issues, such as the legalization of gay marriage in 2017 and a decision in 1992 that reaffirmed a woman's right to an abortion.

His retirement will allow President Donald Trump to make a second nomination to the bench after nominating conservative Neil Gorsuch in 2017. A successful nomination of a similar jurist would tip the balance 5-4 in favor of conservative justices.

Trump said he was considering names from a list of 25 candidates that his campaign collected during his presidential run in 2016. "We have to pick one that's there for 40 years, 45 years," he told a rally in Fargo, North Dakota.

Conservative activists have already announced their intention to use a more conservative court to overturn the 1973 Roe v. Wade decision legalizing abortion in the United States.

Democrat-Republican showdown

The leading Republican lawmaker in the Senate, Mitch McConnell, said the chamber would vote on Trump's nomination in the fall, but he did not say whether it would take place before or after the November midterm elections to the Senate and House of Representatives.

The Republicans control the Senate, which is tasked with approving presidential nominations, 51-49.

Top Senate Democrat Chuck Schumer, however, said Republicans would be hypocritical if they refused to wait until after the midterm elections to hold a vote. Republican senators refused to vote on a Supreme Court justice nominated by former US President Barack Obama before the 2016 presidential election.

Kennedy's resignation, Schumer said, "is the most important Supreme Court vacancy for this country in at least a generation."

amp, es/sms (AP, AFP, Reuters)