Iranian President Hassan Rouhani ordered his defense minister to expedite development of the country’s ballistic missile program in response to new U.S. sanctions set to be imposed on Iranian defense companies. Mr. Rouhani’s comments, made on his official Twitter TWTR 4.09 % account Thursday, cast fresh doubts on the prospects for the U.S. and Iran to successfully implement the landmark nuclear agreement reached last July. The Obama administration has said it could begin removing sanctions on Tehran as early as January since Iran has begun taking steps to roll back its nuclear program. But the U.S. is concurrently preparing to impose new sanctions on Iranian defense firms and officials in the wake of two ballistic missile tests staged by Tehran over the past three months, according to senior U.S. officials. Mr. Rouhani said Thursday such sanctions are illegal and that Tehran will take steps to retaliate, including accelerating the […]