(CNN) - The secretary of the U.S. Senate on Monday rejected the certificiate of appointment for Roland Burris, named by Illinois' controversial governor to fill Barack Obama's Senate seat, according to an aide to the secretary.
The aide said Secretary of the Senate Nancy Erickson rejected Burris' appointment because it does not conform with the Senate rule requiring that the secretary of state - in this case, Illinois Secretary of State Jesse White - must sign the certificate of appointment along with the governor.
White has declined to sign the certificate, siding with some Senate Democrats who say Burris should not be seated because of the cloud over Gov. Rod Blagojevich, who is accused of trying to sell Obama's Senate seat.
According to a Democratic source and a Democratic Senate leadership aide, without the signed certificate Burris will be denied access to the Senate floor.
But Burris insists he has the legal right to serve as senator, and has said he will appear at the Senate's door Tuesday.
"I am going (to Washington) to be seated. I am the junior senator from the state of Illinois - that's all I can say," he said Monday at an airport news conference in Chicago before leaving for Washington.
He said he is not bothered by controversy surrounding his appointment by Blagojevich because "the appointment is legal. What has been done here is legal."
Pressed by reporters on what he would do if he is refused admission to the Senate floor, Burris said, "If I am turned away, my lawyers will take it from there and we'll see what happens."
He said he has not been contacted by anyone from the Obama team, and he insisted that he is not upset at the situation surrounding his appointment.
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"I'm not angry with anybody," Burris said. "In fact, I'm enjoying this on behalf of the people of Illinois."
Senate Democratic leaders have scheduled a meeting with him Wednesday.
Senate Majority Leader Harry Reid said lawmakers have the legal authority to block Burris' appointment, but Reid has also left open the possibility that Burris could be seated.
Burris said he will meet with Reid on Wednesday.
"I will tell him I'm here to take my seat," he said.
Burris, 71, is one of Illinois' most accomplished African-American politicians.
He maintains that the governor's problems have nothing to do with him, and says he's not concerned about the political cloud hanging over his selection.
"I am the duly appointed, legally appointed United States senator from the state ofIllinois, and I certainly expect that the senators will recognize that and do not deny Illinois its equal representation as we get under way in this 111th Congress," he told CNN on Sunday.
"It is my hope and prayer that they will certainly have gotten the message that what the governor has done regarding his problems, they're not my problems, there's no taint on me, he has carried out his constitutional duty and found a person who was qualified to fill that vacancy, and that's what he's done."
Reid said Sunday that Blagojevich's appointment is "tainted," considering the charges against the governor.
"Blagojevich obviously is a corrupt individual. I think that's pretty clear. And the reason that he's done what he's done is to divert attention from the arrest that was just made of him and the indictments that will be coming in a few days according to the U.S. attorney in Illinois," Reid said on NBC's "Meet the Press."
Senate leaders questioning the appointment cite Article 1, Section 5 of the U.S. Constitution, which states, "Each house shall be the judge of the elections, returns and qualifications of its own members."
Those leaders say the problem is that the pick was made by the potentially tainted governor; the problem isn't Burris himself.
Reid said Blagojevich should step down, and then Illinois Lt. Gov. Pat Quinn could name someone - including Burris - to fill Obama's Senate seat.
Asked whether he would refuse to seat Burris should he try to claim a seat in the Senate, Reid responded, "We are going to do what we have to do."
"We're going to follow all legal precedents. ... We're pretty clear on what we believe is the law and the precedent in the United States Senate. ... Democrats and Republicans determine who is going to sit in the Senate," he said.
But Reid left the door open to a possible compromise resolution that might avert a confrontation with Burris and a growing grass-roots effort led by some black politicians and community leaders in Illinois.
Reid said he plans to meet Wednesday with Burris and Illinois' sitting senator, Richard Durbin.
"I'm an old trial lawyer," he told NBC's David Gregory. "There's always room to negotiate."
- CNN's Martina Stewart contributed to this report.