Sen. Bob Corker (R-Tenn.) said Thursday he declined to sign on to a Republican letter demanding an immediate vote on Iran sanctions legislation because he wants to avoid it becoming a partisan issue.

The bill’s 42 other Republican co-sponsors wrote to Senate Majority Leader Harry Reid (D-Nev.) on Thursday demanding he bring up the bipartisan bill. Sens. Rand Paul (R-Ky.) and Jeff Flake (R-Ariz.) have co-sponsored the bill.

Reid has been holding the bill up at the behest of the White House, which argues that passing it could doom nuclear talks.

“It doesn’t diminish my support,” Corker told The Hill. “It’s just that as ranking member on the Senate Foreign Relations Committee, I’d like for us to end up with an outcome that … I want to do what I can to cause it to continue to be an issue that both sides care about.”

The issue has become increasingly partisan in recent weeks, with none of the 16 Democrats on the bill joining Republicans pressing for its immediate passage. Corker placed the blame on Reid, who said he would “support” such a bill last year before backtracking after the Obama administration struck an interim deal in November.

“In some ways, you have to say Sen. Reid has made it a little bit partisan by not allowing us a vote on it when he promised us a vote,” Corker said. “I understand both sides of the equation, but as ranking member on the Senate Foreign Relations Committee, my goal is to ultimately have an outcome where we affect something good happening in Iran.”

He said he’s even approached Foreign Relations Committee Chairman Robert Menendez (D-N.J.), the bill’s author, about possibly bringing up the bill in his committee. The Banking panel, however, has jurisdiction over the issue, and Menendez has not indicated he wants to butt heads with Banking Committee Chairman Tim Johnson (D-S.D.). 

“I understand the frustration on our side of the aisle, and I share it — we haven’t even had a committee markup,” Corker said. “It’s beyond belief: The biggest foreign policy issue our nation is facing, and we can’t even have a committee markup.”

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