Story highlights Sen. Rand Paul denounced House Speaker Paul Ryan's health care bill Wednesday as "a bill of goods"

Paul has been outspoken against the GOP's health care bill

Ryan fired back Wednesday, calling Paul's remarks "insulting"

Washington (CNN) Sen. Rand Paul is firing off on his own party as the health care battle intensifies, accusing House Speaker Paul Ryan on Wednesday of selling "a bill of goods" to the President.

"I think that Paul Ryan's selling him a bill of goods that he didn't explain to the President, and the grassroots doesn't want what Paul Ryan is selling," the Kentucky Republican told CNN.

Paul was one of several lawmakers who took the stage in 20-degree weather outside of the Capitol, rallying conservatives to stand firm against the Republicans' health care bill that's making its way through the House. Conservatives feel that the bill doesn't go far enough in repealing Obamacare.

He urged voters to call other conservative members of the Freedom Caucus and urge them to "bring down the Paul Ryan plan," something he later called "Ryancare" to reporters.

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