Iran’s supreme leader vowed on Thursday that his country would ramp up development of its civilian nuclear program, as major world powers continued delicate talks in Vienna to revive Tehran’s landmark nuclear deal.

In a televised speech, Ayatollah Ali Khamenei urged the importance of nuclear energy for Iran, while again asserting that it had no interest in nuclear weapons.

Khamenei’s remarks seemed clearly aimed at the countries involved in the Vienna talks.

“Enemies are making cruel moves against our nuclear energy issue, (putting) sanctions on nuclear energy that they know is peaceful," he said. “They do not want Iran to achieve this great and significant progress.”

The accord, which former President Donald Trump abandoned nearly four years ago, granted Iran sanctions relief in exchange for curbs on its atomic program. Iran’s chief nuclear negotiator, Ali Bagheri Kani, tweeted late Wednesday that the parties were "closer than ever" to an agreement.

But talks have repeatedly stalled in recent months as Iranian negotiators press hard-line demands, exasperating Western diplomats.

Khamenei, who so far has largely stayed silent on the ongoing negotiations, called claims that Iran was pursuing a bomb “nonsense," saying they were meant to deprive Iran of its legitimate right to nuclear power.

“If we do not pursue (peaceful nuclear energy) today, tomorrow will be late," he said.

Iran long has insisted its nuclear program is peaceful. But the country’s steps away from its obligations under the 2015 accord have alarmed its archenemy Israel and world powers.

Tehran has since started enriching uranium up to 60% purity — a short technical step from the 90% needed to make an atomic bomb, and spinning far more advanced centrifuges than those permitted under the deal.