SPRINGFIELD, Ill. (AP) – U.S. Sen. Mark Kirk says President Barack Obama was “acting like the drug dealer in chief” when his administration delivered $400 million in cash to Iran contingent on the release of American prisoners.

The Republican made the comment to The Springfield State Journal-Register editorial board last week, saying the president can’t be “giving clean packs of money to a … state sponsor of terror.”

Republicans have criticized the Obama administration after it acknowledged that the repayment of the money from a 1970s Iranian account was connected to a U.S.-Iranian prisoner exchange in January. The administration denies the money was “ransom.”

The comment is the latest by Kirk to raise eyebrows in his re-election campaign against Democratic U.S. Rep. Tammy Duckworth. A Duckworth spokesman accused Kirk of “disgracefully insulting” the president.