Iran has begun enriching uranium at its underground Fordow site in the latest breach of its deal with major powers, the U.N. nuclear watchdog confirmed on Monday, adding that Tehran’s enriched uranium stock has continued to grow.

Iranian forces shot down a foreign drone over the port city of Mahshahr in its southern Khuzestan province on Friday, state news agency IRNA reported, quoting an Iranian official.

U.N. nuclear inspectors are on the ground in Iran and will report back on relevant activities, an International Atomic Energy Agency spokesman said on Wednesday after Iran said it injected uranium gas into centrifuges at its Fordow site.

Iran will start injecting uranium gas into centrifuges at its underground Fordow enrichment facility, Iranian President Hassan Rouhani said on Tuesday, a highly symbolic breach that will complicate European efforts to salvage Tehran’s nuclear deal.

Kuwait’s deputy foreign minister Khaled al-Jarallah said on Tuesday that Kuwait conveyed messages from Iran to Saudi Arabia and Bahrain regarding the situation in the Gulf region, and “until now no answers have emerged”.

Iran said on Monday it had launched a new batch of advanced centrifuges to accelerate uranium enrichment, further reducing compliance with the 2015 nuclear deal following the withdrawal of its arch-foe the United States.

Iran said Saturday it has sent Iraq and Arab states of the Gulf the text of its security and cooperation project first unveiled by President Hassan Rouhani at the UN in September.

The United States said on Thursday it had imposed sanctions on the Iranian construction sector and trade in four materials used in its military or nuclear programs, even as it waived sanctions to let foreign firms continue non-proliferation work in Iran.

The United States on Friday asked foreign governments to submit detailed reports on humanitarian exports to Iran, a step observers said could have a chilling effect and cast a pall over European efforts to allow trade.

A senior Saudi official said on Thursday that a policy of appeasement would not work with Iran and that the only way to get Tehran to the negotiating table was to apply maximum pressure.

Iranian Foreign Ministry spokesman Abbas Mousavi regretted Bahrain's invitation of Israeli delegation to participate in security conference in Manama.

Representatives from more than 60 countries including Israel but not Iran met in Bahrain on Monday to discuss maritime security following attacks on tankers in the Gulf and Saudi oil installations.

The U.S. State Department said on Thursday it has extended by 120 days a waiver to sanctions allowing Iraq to import gas and electricity from Iran as it pushes Baghdad to make the country more energy independent.

Pakistani Prime Minister Imran Khan met Saudi Arabia's King Salman on Tuesday, Saudi state media reported, two days after he visited Iran on a mission to defuse tensions between Riyadh and Tehran.

Iran’s President Hassan Rouhani said an Iranian tanker damaged in the Red Sea on Friday had been hit by at least two rockets, and there is video footage of the incident.

A Saudi minister said on Sunday that Riyadh was not behind a suspected strike against an Iranian-owned oil tanker in the Red Sea, which Iranian state-run television said was hit on Friday by missiles but denied reports they came from Saudi Arabia.

Saudi Arabia's crown prince warned in an interview broadcast on Sunday that oil prices could spike to "unimaginably high numbers" if the world doesn't come together to deter Iran, but said he preferred a political solution to a military one.

Saudi Arabia has sent messages to Iran's president through the leaders of other countries, an Iranian government spokesman said on Monday, at a time of heightened tensions between the regional rivals.

Iraq reopened its Qaim border-crossing with Syria on Monday after eight years of closure amid regional turmoil, in the latest sign of normalization between Baghdad and Damascus and a win for their mutual ally Iran.

Iran has committed another breach of its nuclear deal with major powers by enriching uranium with advanced centrifuges, a report by the U.N. nuclear watchdog policing that deal said on Thursday, further fraying the landmark accord.