WASHINGTON (AP) -- The Supreme Court turned down an appeal Monday that sought to open U.S. presidential elections to voters in Puerto Rico.

The court's action, taken without comment, is the latest setback in a long-running legal fight over voting rights of residents of the U.S. territory.

Attorney Gregorio Igartua, who filed the appeal, said that "for 107 years and 22 presidential elections since Puerto Rico became part of the United States, the American citizens of Puerto Rico" have been unfairly treated. He told justices that the residents have "an inferior type of American citizenship."

The 1st U.S. Circuit Court of Appeals had ruled against Igartua, saying the United States must amend the Constitution, or Puerto Rico must become a state before its residents can vote for president.

The Bush administration's top Supreme Court lawyer said in a filing that the appeals court decision "is amply supported by constitutional text, unbroken tradition and uniform precedent."

"No territory has ever participated in any of the 54 presidential elections conducted over more than two centuries of American history," Solicitor General Paul Clement wrote.

Copyright 2006 The Associated Press.