Sen. Chris CoonsChris CoonsCoons: Senate may have to 'support military action' A Vandenberg movement in Congress Senate approves Trump's Agriculture chief MORE (D-Del.) is calling for President Obama to move forward with new sanctions against Iran over a pair of recent ballistic missile tests.
"I don't know why the administration has hesitated, but I am urging them publicly and privately to move ahead with those designations," he told reporters. "I am concerned with the hesitation to move forward with the ballistic missile related designations."
The Obama administration suggested late last year that it was preparing new sanctions against individuals tied to Iran's missile program, before walking back those statements.
Iran quickly hit back, calling the proposed sanctions "illegal."
Coons, who supported the Iran nuclear deal, said it was "very clearly communicated and it played a role in my decision" to support the nuclear agreement that the United States was still able to sanction Iran on non-nuclear issues including its missile program or support for terrorist groups.
The administration has gotten bipartisan criticism over its handling of the Iranian missile tests, which lawmakers say violate United Nations Security Council resolutions.
The scuffle comes as the international community is speeding toward "implementation day" of the separate nuclear deal, when the administration will lift sanctions against Iran.
Senate Republicans are calling on Obama to block lifting sanctions under the deal because of the recent ballistic missile tests, rejecting the administration's argument that the two are separate issues. The move would likely undermine the nuclear agreement.