Iran’s stock of uranium close to weapons grade has jumped since it announced a dramatic acceleration in enrichment in December and there has been no progress on resolving outstanding issues, two reports by the U.N. nuclear watchdog said on Wednesday.

The stock of uranium enriched to up to 60% fissile purity, close to the roughly 90% of bomb grade, has been a long-standing concern for Western powers, which say there is no civil justification for enriching uranium to such a high level. Iran says it seeks only peaceful nuclear energy, Reuters reported.

While U.S. President Donald Trump’s administration has said it plans to pressure Iran over its nuclear programme, the International Atomic Energy Agency has said time is running out for diplomacy to impose new restrictions on Iran’s activities.

“The significantly increased production and accumulation of high enriched uranium by Iran, the only non-nuclear weapon state to produce such nuclear material, is of serious concern,” the International Atomic Energy Agency said in a passage that, unusually, was included in both its quarterly reports on Iran.

Those confidential reports, sent to member states on Wednesday and both seen by Reuters, showed that while the stock of 60% material grew by half, there was no real progress on resolving long-running outstanding issues including the unexplained presence of uranium traces at undeclared sites, read the report.

The stock of uranium refined to up to 60% in the form of uranium hexafluoride grew by 92.5 kg in the past quarter to 274.8 kg, one of two confidential IAEA reports said.

That is enough in principle, if enriched further, for six nuclear bombs, according to an IAEA yardstick. There is enough for more weapons at lower enrichment levels.

Where before its latest acceleration Iran was producing between 6 and 9 kilograms (13 and 20 pounds) of uranium enriched to up to 60% per month, now that figure is between 35 and 40 kg, a senior diplomat said. This is just short of the 42 kg that is enough in principle for one bomb, if refined further.

One of the reports spelled out the lack of progress on the outstanding issues such as explaining the uranium traces, which the IAEA has been asking the Islamic Republic to do for years.

“Iran states that it has declared all of the nuclear material, activities and locations required under its Safeguards Agreement. This is inconsistent with the Agency’s assessments,” it said.

“The Agency is, therefore, at an impasse with regard to resolving these outstanding safeguards issues.”

During his first, 2017-21 term as president, Trump withdrew the United States from a landmark deal between Iran and major powers that placed strict limits on Tehran’s nuclear activities in exchange for sanctions relief. After Trump pulled out in 2018, Iran breached and far surpassed those limits, Reuters reported.

With the deal now largely in tatters, European powers are seeking to either have the U.S. help agree new limits on Iran’s nuclear programme or use a mechanism in the deal to re-impose all sanctions before the deal expires in October.

Russian Foreign Minister Sergei Lavrov and Iran’s top leaders aligned positions on issues around Iran’s nuclear programme at talks in Tehran on Tuesday, Russia’s Foreign Ministry said.

Lavrov discussed a wide range of bilateral and regional issues with both President Masoud Pezeshkian and his Iranian counterpart Seyed Abbas Araghchi, a ministry statement said.

“Positions were aligned on the situation around the Joint Comprehensive Plan of Action on the Iranian Nuclear Programmе,” it said.

Russia is a signatory of the 2015 JCPOA deal alongside the U.S., China, France, Britain and Germany. The deal lifted sanctions on Iran in exchange for curbs on its nuclear activities

Lavrov had earlier said in Tehran that Moscow was sure that diplomatic measures were still on the table when it came to resolving issues around Iran’s nuclear programme.

Rafael Grossi, director general of the International Atomic Energy Agency, the U.N. nuclear watchdog, said last week that Iran continued to enrich uranium well beyond the needs for commercial nuclear use despite U.N. pressure to stop it.

Grossi told Reuters that while the pace of uranium enrichment had slowed slightly since the end of last year, Iran was still enriching at an elevated rate of around 7 kg of uranium per month to 60% purity.

Iran denies seeking nuclear weapons but no other state has enriched to that level without producing them.

Grossi said he wanted to visit Tehran next month for the first time in a year.

Russia and Iran have drawn closer in recent years, with Iran supporting Russia in its military campaign in Ukraine. The two sides signed a strategic partnership agreement in January.

Lavrov discussed a wide range of bilateral and regional issues during his visit, including Syria, Lebanon and Afghanistan and the Israel-Palestine conflict, the Russian foreign ministry said.

Russian news agencies reported that Lavrov later travelled on to Qatar.

Russia’s Foreign Minister Sergei Lavrov landed in Tehran on Tuesday for talks with Iranian officials, Iranian state media reported.

This comes days after Moscow held initial talks with the US just a month after Donald Trump returned to the White House.

Lavrov will discuss regional and bilateral topics with his Iranian counterpart during his one-day trip to Iran, Russian state media reported.

The visit comes a day after the United States imposed a fresh round of sanctions targeting Iran’s main source of income, the oil industry.

Trump earlier this month had restored his “maximum pressure” campaign on Iran that includes efforts to drive the country’s oil exports to zero, reimposing Washington’s tough policy on Iran that was practiced throughout his first term, Reuters reported.

Russia’s media reported that the main focus of their discussions is expected to be on expanding trade and economic cooperation, particularly in the energy and transportation sectors.

The ministers are also however planning to exchange views on a number of international issues, including the situation in Syria, the Caucasus, Afghanistan, Yemen, the Persian Gulf region, the Caspian Sea issue, and the prospects for the Joint Comprehensive Plan of Action on Iran’s nuclear program.