Iran will reject a US proposal to end a long-running dispute over nuclear program of Tehran, an Iranian diplomat said today, arguing that it has no chance of success, does not serve Tehran’s interests, while Washington’s position on uranium enrichment remains unchanged.

“Iran is drafting a negative response to the U.S. proposal, which could be interpreted as a rejection of the proposal,” a senior diplomat close to Iran’s negotiating team told Reuters.

The U.S. proposal for a new nuclear deal was presented to Iran on Saturday by Omani Foreign Minister Sayyid Badr Albusaydi, who paid a brief visit to Tehran and is mediating talks between Tehran and Washington.

But after five rounds of talks between Iranian Foreign Minister Abbas Araghchi and President Donald Trump’s special envoy, Steve Whitcoff, to resolve the nuclear standoff, many issues remain unresolved.

Among the conflicting red lines, Iran’s rejection of a U.S. demand that Tehran commit to eliminating uranium enrichment, seen as a possible path to nuclear bomb development.

Tehran says it wants to perfect nuclear technology for peaceful purposes and has long denied accusations by Western powers that it is seeking to acquire nuclear weapons.

“In this proposal, the US position on enrichment on Iranian soil remains unchanged, and there is no clear explanation in terms of lifting sanctions,” said the diplomat, who asked not to be named.

Tehran is demanding the immediate lifting of all restrictions imposed by the US that are suffocating its oil-dependent economy. But for the US, lifting sanctions linked to Iran’s nuclear program will have to be done in stages.

Dozens of Iranian institutions critical to Iran’s economy, including the central bank and the national oil company, have faced sanctions since 2018 for “supporting terrorism or nuclear proliferation,” according to Washington.

Trump‘s revival of his campaign of putting “maximum pressure” on Tehran after his return to the White House in January includes tougher sanctions and threats to bomb Iran if current negotiations fail to reach a deal.

During his first term, Trump withdrew the US from the 2015 deal between Tehran and six powers and reinstated sanctions. In response, Tehran quickly violated the restrictions on its nuclear program imposed by the 2015 deal.

The 2015 agreement required Iran to take steps to curb its nuclear program in exchange for relief from U.S., EU and U.N. sanctions.

The diplomat said Iran’s “committee for nuclear negotiations” under the supervision of Supreme Leader Ayatollah Ali Khamenei believes the US proposal is “completely one-sided” and cannot serve Tehran’s interests.

Therefore, the diplomat said, Tehran believes the proposal has no chance of success and believes that with it the US is unilaterally trying to impose a “bad deal” on Iran through excessive demands.

Two Iranian officials told Reuters last week that Iran could stop enriching uranium if the U.S. released Iranian funds and recognized Tehran’s right to enrich uranium for civilian use under a “political agreement” that could lead to a broader nuclear deal.