(CNN) House Speaker Paul Ryan was pressed Thursday at a CNN town hall on the Republican push to block Planned Parenthood from receiving federal health care dollars for services provided to women because the organization provides abortions.

"We don't want to commit taxpayer funding for abortion, and Planned Parenthood is the largest abortion provider," he said.

Moderator Jake Tapper pressed Ryan, noting that existing law blocks taxpayer dollars from funding abortions. But, Ryan argued, "money's fungible, and it effectively floats these organizations."

He said Republicans would rather shift those dollars -- and redirect Planned Parenthood's patients using those dollars -- to federal community health centers.

"You don't have these controversies by funding health centers," he said.

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