U.S. President Donald Trump has finished interviewing candidates for a Supreme Court seat, Fox News reported Thursday.

According to the news channel, the president has interviewed six candidates, namely appeals court judges Brett Kavanaugh, Raymond Kethledge, Amy Coney Barrett, Amul Thapar, Joan Larsen and Thomas Hardiman.

Trump's top contenders for the vacancy are Kavanaugh, Kethledge and Barrett, according to reports.

U.S. Supreme Court Justice Anthony Kennedy, the court's current longest-serving member and second-oldest justice, announced last week that he is retiring.

Kennedy is widely thought to be a moderate and pivotal swing vote in the highest federal court.

Liberal advocacy groups and others are concerned that Trump's pick to fill Kennedy's seat would move the court more solidly to the right.

Trump is expected to make an announcement on Monday.