Iran's economic transformation rests with domestic issues and not with ongoing nuclear negotiations, Supreme Leader Ali Khamenei said Wednesday.

U.S. Secretary of State John Kerry met Tuesday in New York City with his Iranian counterpart, Javad Zarif, to review progress on nuclear talks. State Department spokesman Jeff Rathke said the meeting "was productive."

The five permanent members of the U.N. Security Council, plus Germany, are working with their Iranian counterparts to formalize a framework agreement that pulls Iran back from the brink of having the technology needed to develop a nuclear weapon.

Iran is restricted to around 1 million barrels per day in exports to a few consuming nations. That's about half the level from before a joint arrangement went into force in late 2013, though Iranian officials said they're working to lessen the economic dependency on oil revenue.

Khamenei said Wednesday economic momentum rests not at the negotiating table, but at home.

"The key to the settlement of problems is not in Lausanne, Geneva and New York [that have hosted most rounds of Iran-powers nuclear talks], rather the key is in the country and all people should act upon their different responsibilities to strengthen domestic production as the only remedy for economic problems," he said.

Iran's economy emerged from recession in late 2014, though sanctions still curb the country's ability to generate revenue from oil and gas sales. The Central Bank of Iran, however, said a nine-month growth rate of 3.6 percent represents an increase of $54 billion.

Despite the emphasis on domestic solutions, Iranian business directors said foreign investments are needed to help with developing of aging oil fields in the Islamic republic.