Three leading conservative gun-rights senators on Thursday slapped President Obama for using the Newtown Elementary School slayings to push gun control, and warned that they will demand 60 votes in the Senate for anti-gun legislation to proceed.

In a release following the president's latest gun comments, Utah Sen. Mike Lee said that he, Texas Sen. Ted Cruz and Kentucky Sen. Rand Paul have informed Senate Majority Leader Harry Reid that they will require a 60-vote threshold to advance new gun legislation.

Unofficial vote counts indicate that there are not 60 votes in the Senate to OK some of the controversial elements of the president's plan, including an assault weapon ban.

From Lee's statement:

"Along with my colleagues Rand Paul of Kentucky and Ted Cruz of Texas, I have informed the Majority Leader that we will exercise our procedural right to require a 60-vote threshold in order to bring any of the president's proposals to the floor. We have done this for three reasons:

"First, as we saw last week with a vote on my amendment to establish a two-thirds requirement for the passage of any new gun legislation, virtually all Republicans and at least six Democrats believe that new gun legislation should have overwhelming bipartisan support in the Senate before it becomes law.

"Second, this debate is about more than magazine clips and pistol grips. It is about the purpose of the Second Amendment and why our constitutionally protected right to self-defense is an essential part of self-government. Any legislation that would restrict our basic right to self-defense deserves robust and open debate. Requiring a 60-vote threshold helps ensure that we have that debate rather than skipping directly to the back room deals, horse trading, and business-as-usual politics that typifies the way Congress passes legislation today.

"Finally, many of the current gun proposals are constitutionally problematic. Altering the application of constitutional protections should require approval by a supermajority of Congress. With a 60-vote threshold, we are seeking to ensure that a bare majority does not jeopardize the basic rights of the American people.

"The Senate -- and the American people -- have an important debate ahead of us. I look forward to this debate and hope that others Senators join me, Rand Paul, and Ted Cruz in demanding that our discussions take place in full view of the American people."