U.S. lawmakers on Monday, April 16, pushed for more sanctions against Iran after talks between Tehran and global powers failed to stop Iran from developing its nuclear program, Reuters reported. Although the talks between Iran and six world powers were described as “constructive” by the European Union’s foreign policy chief, Catherine Ashton, some U.S. lawmakers said they were unimpressed. Senator Mark Kirk (R-IL) and several other U.S. legislators have been pressuring the White House to get tougher on Iran and are pushing for a range of additional penalties against the Islamic Republic. “We have five weeks to convince the Iranians that the sanctions we passed in December were only a first step,” said Senator Robert Menendez (D-NJ), who along with Kirk helped design the sanctions that were signed into law in December.