(Bloomberg) -- Russia’s chief negotiator for Iran nuclear talks estimated it will take more time to reach an agreement than he previously thought possible, as the U.S. warns that the window for saving the accord is closing. 

“If the talks continue at the pace they’re currently going, in principle it’s quite realistic to reach agreement by the end of February,” Mikhail Ulyanov told Rossiya-24 on Wednesday night, adding that a deal could be implemented by April. Last month he said he thought it would be possible to conclude talks to restore the deal by early February. 

U.S. President Joe Biden said last week that it’s “not time to give up” on reviving the Iran accord, which unraveled after the Trump administration quit it in 2018 and reimposed sanctions. At the same time, U.S. Secretary of State Antony Blinken said earlier this week that negotiations to revive the deal, now in their eighth round, cannot be allowed to drag on too long.  

Ulyanov said Iran may start direct talks with the U.S. “rather soon” and that a restored deal will lift Washington’s sanctions on the Islamic Republic’s oil exports. He didn’t specify whether that meant a new accord would restore sanctions waivers for Iranian oil, or lift the penalties altogether. 

Iran and world powers have been struggling to resolve some key differences over how to restore the 2015 accord, whose disintegration provoked Tehran to significantly advance its atomic activities. If they manage to resurrect the agreement, the U.S. would be expected to lift its sanctions on Iran, making it easier for it to sell oil on global markets, a key source of income.

Earlier this week, Iran’s foreign minister and a top security official raised the possibility of direct talks with the U.S. if Tehran senses that a “good” deal is within reach.

Iran May Consider Direct U.S. Talks Over Nuclear Guarantees (1)

In Tehran, however, hardliners close to Iran’s Supreme Leader Ayatollah Ali Khamenei appeared to reject that position after the leading ultraconservative Kayhan newspaper admonished the Secretary of the Supreme National Security Council, Ali Shamkhani, earlier this week for appearing to leave open the possibility of direct talks with the U.S.  

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