Tougher sanctions won't convince Iran to stop enriching uranium, former American diplomat Ryan Crocker told the Los Angeles Times on Saturday.
Instead, Crocker maintains US President Barack Obama should step up diplomacy and consider concessions to the Islamic Republic.
"Sanctions are easy to do, and afterwards we can tell ourselves that, 'By God, we've really stuck it to them.' But it seems to me that the more you press this regime, the more they dig in," Crocker told the LA Times.
Crocker served as US ambassador to Iraq, Afghanistan, Pakistan, Syria, Lebanon and Kuwait. He was awarded the Presidential Medal of Freedom, and is a member of a bipartisan group called the Iran Project that is pushing the White House and Congress to change course in order to persuade Iran to halt it nuclear program.