"A nation that is not strong will be oppressed," Khamenei, the country's top decision-maker, said today in the northeastern city of Mashhad in an address in honour of the Persian New Year.
"The extortionists in the world will blackmail a weak nation, insult it, attack it, and trample it under their feet," he said in remarks broadcast live on state television, in an apparent reference to the United States and other Western powers.
Hopes for an economic recovery were rekindled after President Hassan Rouhani took office in August with a promise to repair relations with the world. In November he clinched an interim nuclear deal with world powers that brought modest sanctions relief.
But Khamenei, who has the final say on the nuclear issue, said Iran should not pin its hopes on "when the enemy will lift the sanctions," alluding to nuclear talks with world powers aimed at reaching an ambitious final accord by July 20.
In return, they would lift sanctions that have stoked double-digit inflation and high unemployment, and which have more than halved the country's vital oil exports.