Chuck Grassley, the chairman of the Senate Judiciary Committee, said a Supreme Court justice could resign as soon as this summer.
"I would expect a resignation this summer," said Grassley, R-Iowa, according to The Muscatine Journal. His comments came during a Q&A at a visit to the Kent Corp. in Muscatine in his home state.
Without naming a justice, he said an upcoming resignation is "rumored."
The oldest justices on the court are Ruth Bader Ginsburg, 84; Anthony Kennedy, 80; and Stephen Breyer, 78.
If one of those justices resigns — Ginsberg and Breyer are viewed as liberal, and Kennedy is the court's swing vote — President Trump will likely nominate a more conservative judge as a replacement, tilting the court to the right.
The court is back at full attendance with nine sitting justices, after Neil Gorsuch was sworn in on April 10 as the 113th Supreme Court justice.
This year, the Senate faced a bitter battle over replacing the late Justice Antonin Scalia's seat on the nation's highest court. In pushing Gorsuch through the confirmation process, Senate Majority Leader Mitch McConnell invoked what was called the nuclear option, lowering the threshold from 60 votes to 51 to confirm Supreme Court nominees.