Iran yesterday defended its "right" to enrich uranium despite growing Western concern that Tehran may be seeking nuclear weapons, and as talks with the United States were delayed.

Foreign Minister Abbas Araghchi said in a post on X that "Iran has every right to possess the full nuclear fuel cycle," citing Tehran's long-standing membership of the Nuclear Non-Proliferation Treaty (NPT).

"There are several NPT members which enrich uranium while wholly rejecting nuclear weapons," Araghchi said.

Under the NPT, signatory states are obliged to declare their nuclear stockpiles and place them under the supervision of the UN's nuclear watchdog, the International Atomic Energy Agency (IAEA).

The United States and other Western countries have long accused Iran of pursuing nuclear weapons -- a claim Tehran denies.

Iran and the United States have engaged in nuclear talks since April 12, their highest-level contact since Washington withdrew from a landmark deal with Tehran in 2018.

A fourth round of talks initially scheduled for yesterday has been postponed, mediator Oman said earlier this week, citing "logistical reasons".

In a Thursday interview with Fox News, US Secretary of State Marco Rubio called on Iran to "walk away" from enrichment."

Iran currently enriches uranium to 60-percent purity -- far above the 3.67-percent limit set in the 2015 deal with the United States and other world powers, but below the 90 percent needed for weapons-grade material.