Supreme Court Justice Antonin Scalia was remembered Saturday at a funeral mass capping two days of mourning for a jurist who left a long and sometimes controversial legacy on the nation.

Scalia's son Paul -- a Catholic priest -- led the service and mixed humour and reverence for the conservative icon and father of nine who died unexpectedly last weekend.

"Sure, he forgot our names at times or mixed them up, but there are nine of us," Scalia told thousands of mourners at the Basilica of the National Shrine of the Immaculate Conception.

"He loved us and sought to show that love and sought to share the blessing of the faith he treasured," Scalia said.

President Barack Obama did not attend Saturday's funeral, despite criticism from some Republicans. He and first lady Michelle Obama were among the more than 6,000 people who paid tribute to Scalia on Friday at the Supreme Court, where he lay in repose.

USA-COURT/SCALIA

U.S. President Barack Obama and first lady Michelle Obama walk past a portrait of U.S. Supreme Court Justice Antonin Scalia after paying their respects at his casket in Washington on Friday. (Kevin Lamarque/Reuters)

Scalia's flag-draped casket rested on a funeral bier that first held President Abraham Lincoln's casket after his assassination.

Scalia's sons and sons-in-law served as pallbearers when his casket arrived at the basilica.

Dignitaries including Vice-President Joe Biden, former vice-president Dick Cheney, members of Congress and all eight sitting justices of the Supreme Court were among those attending.

Several federal judges who are considered possible replacements for Scalia also attended, including Judges Sri Srinivasan and Patricia Millett and Chief Judge Merrick Garland, all of the U.S. Court of Appeals for the District of Columbia Circuit.

Scalia, 79, died last weekend at a remote Texas ranch after spending nearly three decades on the high court. Burial plans have not been announced.

GOP presidential hopeful Ted Cruz interrupted his campaign ahead of Saturday's South Carolina primary to attend the mass. The Texas senator has been among those urging the Senate not to consider replacing Scalia until after the November election. Obama has insisted that he will nominate a successor.

Washington's archbishop Cardinal Donald Wuerl delivered opening remarks at the service.

Three popes have visited the basilica: Pope John Paul II in 1979, Pope Benedict XVI in 2008 and Pope Francis last year.