President Hassan Rouhani, responding to domestic critics, said Wednesday Iran's foreign policy is in the hands of the government only, ISNA news agency reported.
The president's moderate views on recent nuclear talks and foreign policy have clashed with ultraconservative factions in the regime.
But he has so far enjoyed the qualified support of Supreme Leader Ayatollah Ali Khamenei, who has the final say on all state matters.
"The government is in charge of foreign policy and... makes decisions about it within the framework of the supreme leader's policies and no one else can interfere," said Rouhani.
"Political infighting and clashes which create tension in society and have (an adverse) impact on economic activities are not acceptable," Rouhani said during a visit to oil-rich Khuzestan province.
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Western powers had slapped Iran with crippling sanctions over suspicions it is using its nuclear activities to produce an atomic bomb. Tehran has repeated denied that, insisting its programme is peaceful.
Iran and major world powers clinched a historic nuclear deal in November.
In a major achievement for Rouhani, Tehran agreed to curb parts of its nuclear drive for six months in exchange for modest sanction relief and a promise by Western powers not to impose new measures on its economy.
Rouhani won a first-round electoral victory over a pool of conservatives last year. He was elected with the vow of a more diplomatic approach with the West after eight years of stalled talks and escalating sanctions under hardline predecessor Mahmoud Ahmadinejad.
"Some people... ask what is (the use of) confidence-building smiles and constructive interaction. It is for the progress of the country," Rouhani said.
Some of his ministers have been repeatedly summoned to parliament over their stances, and some MPs have asked to have a formal seat in the nuclear talks with world powers.