WASHINGTON — Speculation has been humming around Capitol Hill in recent weeks about a successor to 90-year-old Democratic U.S. Sen. Robert Byrd if he steps down as chairman of the powerful Senate Appropriations Committee.

But the first in line to succeed him, U.S. Sen. Daniel K. Inouye of Hawai'i, doesn't want to be part of it.

"It is demeaning to leader Byrd and the U.S. Senate to have this media frenzy focusing on leadership succession of the appropriations committee," Inouye, a Democrat, said in a statement issued today.

"I will not engage in this sort of discussion when we already have a leader in place."

But if Inouye becomes chairman, he would preside over a committee that decides how billions of federal dollars are spent annually.

For Hawai'i, it means the senator could build on his successes in steering hundreds of millions a year to the state for various projects from healthcare to brown tree snake control.

First elected to the Senate in 1958, Byrd, of West Virginia, is the longest serving senator in U.S. history. He has chaired the committee off and on since 1989, whenever Democrats were in the majority.

But the senator has had health problems since falling at his Virginia home in February and developing infections from his medication during his recovery.

A flurry of media reports said those health problems have led some Democrats to quietly question his ability to serve in the high-profile position during the upcoming battles with Republicans and the White House over spending bills for the Iraq and Afghanistan wars.

Some stories also said Senate leaders have asked Inouye, now chairman of the Senate Appropriations Defense Subcommittee and the Senate commerce committee, if he would take the appropriations chairmanship for the remainder of the year if Byrd stepped aside.

Once the publicity started, senators, including Majority Leader Harry Reid of Nevada, have been quick to back up Byrd.

"As long as Senator Byrd can function and wants to, he's the chairman. So I'm not one of those who wants to speculate about what to do if the chair is open," U.S. Sen. Frank Lautenberg said today.

"There is a structure here that says seniority governs. So I don't know who would be second or third, but I'm not looking at that," he said.

Inouye, a longtime friend of Byrd, said today that if a problem comes up in dealing with appropriations committee business, "we all step in to help."

For example, Inouye has filled in for Byrd on an Appropriations Homeland Security Subcommittee hearing and other appropriations committee members such as U.S. Sens. Patty Murray, D-Wash., and Patrick J. Leahy, D-Vt., have done the same.

Inouye, 83, who has climbed the rungs of Senate leadership since entering the chamber in 1963, said he believes in the Senate's seniority system, which primarily governs succession in committees.

"The seniority system has worked throughout the Senate's history," he said. "It provides a modicum of decorum."

Raju Chebium of Gannett News Service contributed to this report.