Iran's new President Hassan Rowhani called Saturday for a foreign policy free of damaging sloganeering as Foreign Minister Mohammad Javad Zarif took office.
Rowhani said the clear message from voters, who gave him a surprise election victory over five conservatives on June 14, was that they wanted a new, more rational foreign policy.
"Foreign policy is not carried out by repeating slogans," Rowhani said, in a clear allusion to the fiery rhetoric of his hardline predecessor Mahmoud Ahmadinejad, which brought international isolation.
"We have no right to use foreign policy to win plaudits -- it's a very sensitive field and it's the key to solving our current problems," the ISNA news agency quoted him as saying at a foreign ministry handover ceremony.
Rowhani -- a moderate cleric and former nuclear negotiator -- has made easing the Western sanctions that have crippled Iran's economy through more constructive diplomatic engagement his signature platform.
"One of the messages of the voters in the presidential election was that they wanted a change in foreign policy," he said.
"That doesn't mean abandoning our principles but it does mean a change of method.
"We are going to strongly defend our national interests but that has to be done appropriately, precisely and rationally," the president said.
"The public will pay dearly for any foreign policy mistake."
Rowhani has said he is ready to hold "serious" talks with the major powers without delay to allay Western concerns about Iran's nuclear programme.
Western governments suspect that the programme is cover for a drive for a nuclear weapons capability, despite Tehran's repeated denials.