U.S. Treasury Secretary Janet Yellen has issued a warning that Iran's April 14 missile attack against Israel could lead to "economic spillover," including further sanctions. 

“Treasury will not hesitate to work with our allies to use our sanctions authority to continue disrupting the Iranian regime’s malign and destabilizing activity,” she said in a news release on April 16. “I fully expect we will take additional sanctions actions against Iran in the coming days.”

Yellen denounced Iran's attack in that release, highlighting how the U.S. has been "responding to challenges in the Middle East." Between the missile attack and Iran-backed Houthi rebel attacks on vessels in the Red Sea, Yellen is concerned that "Iran's actions threaten the region's stability and could cause economic spillover." 

Existing sanctions currently ban almost all U.S. trade with Iran and block the Iranian government's assets in the U.S. 

The potential fallout from the growing conflict between Iran and Israel is likely to be high on the agenda at the International Monetary Fund and the World Bank's annual spring meetings April 17-19, which Yellen will attend. Yellen also says she will meet with U.S. allies during those meetings to address the global economic outlook on conflicts in both the Middle East and Ukraine.