President Barack Obama is coming under pressure from his own party to advance new penalties to punish Iran for its recent ballistic missile tests even as a landmark nuclear deal, which would loosen international sanctions, is on the verge of being implemented.<br />Several Democratic senators who supported the deal say they’re worried that the Obama administration’s delay in issuing new sanctions may undermine the U.S.’s ability to enforce the agreement.<br />Bob Casey, a Pennsylvania Democrat on the Senate Finance Committee, and Chris Coons, a Delaware Democrat who’s a member of the Senate Foreign Relations panel, said Monday they want the administration to move forward with additional sanctions after the missile tests that Iran conducted late last year.<br />Both senators supported the July agreement that would ease economic sanctions on Iran in exchange for curbs on the country’s nuclear program.