The national security adviser of the United Arab Emirates met Monday with Iran’s hard-line president in Tehran, a major visit for the Gulf Arab federation that has long viewed the Islamic Republic as its main regional threat.

The visit by Sheikh Tahnoon bin Zayed Al Nahyan comes as the Emirates and Saudi Arabia are both negotiating with Iran amid efforts in Vienna to save Tehran’s tattered nuclear deal with world powers.

The UAE, home to Abu Dhabi and Dubai, reached a diplomatic recognition deal last year with Israel, increasing tensions with Tehran. The UAE has long served as a lifeline to the outside world for Iran amid international sanctions.

Sheikh Tahnoon, wearing a navy-blue thobe, black suit jacket and his signature aviator sunglasses, met first with Ali Shamkhani, the head of Iran’s Supreme National Security Council. The two men smiled and shook hands in front of journalists before their meeting, a large map of Iran and the Persian Gulf looming behind them, with just a sliver of the Emirates visible on it.

Iranian state television quoted Shamkhani as saying that “warm and friendly” relations between the countries remain a priority and that they shouldn’t be affected by other nations — likely a reference to the United States and Israel.

Sheikh Tahnoon later met with President Ebrahim Raisi, a hard-line protégé of Supreme Leader Ayatollah Ali Khamenei. A statement from the presidency quoted Raisi as welcoming “improved ties with the Emirates,” including on economic issues.

“There should be no barrier in relation of the two Muslim nations of Iran and the Emirates,” Raisi said. “It should not be affected by foreigners’ dictation.”

The Iranian presidency quoted Sheikh Tahnoon as inviting Raisi for a state visit to the UAE. A report by the UAE’s state-run WAM news agency did not mention the invitation, but said the two “discussed prospects of consolidating bilateral ties and explored an array of issues of common interest.”

Monday marked a series of political visits in the region against the backdrop of the Vienna talks in Europe. Syria’s Foreign Minister Faisal Mekdad also visited Tehran, and Saudi Crown Prince Mohammed bin Salman was to visit Oman on a regional tour. Meanwhile, Turkish President Recep Tayyip Erdogan was to travel to Qatar, which Prince Mohammed also planned to visit soon.

Sheikh Tahnoon’s brother is Sheikh Mohammed bin Zayed Al Nahyan, Abu Dhabi’s powerful crown prince and long the de facto ruler of the Emirates, a federation of seven sheikhdoms. Under Sheikh Mohammed, the UAE has embarked on a rapid expansion of its military forces to counter what they see as the threat of Iran. The Emirates also hosts U.S. and French forces and its Jebel Ali port is the U.S. Navy’s busiest port of call outside of America.

Sheikh Tahnoon also has held at least one meeting with the head of the Israeli Mossad intelligence service.

Sheikh Mohammed has long feared a nuclear-armed Iran, according to U.S. diplomatic cables published by WikiLeaks.

But the UAE has pulled back from the Saudi-led war in Yemen against the Iranian-backed Houthi rebels. Since the outbreak of the coronavirus pandemic, the Emirates also has sought to mend diplomatic ties to Turkey, viewed with suspicion over offering a haven for Islamists, and Qatar, which the UAE boycotted for years with several other nations as part of a political dispute.

Ali Bagheri Kani, an Iranian deputy foreign minister leading the Vienna talks, also recently traveled to the UAE for talks.

As the meeting took place, however, Iranian Foreign Ministry spokesman Saeed Khatibzadeh criticized the Emirates for its purchase this past weekend of 16 billion euros worth of advanced Rafale jet fighters from France. The UAE also plans a $23 billion purchase including advanced stealth F-35 fighters as well, after its recognition of Israel.

Khatibzadeh urged France to “behave more responsibly” and criticized the “militarizing of our region.”

“We are witnessing billions of dollars of arm sales to regional countries though they hold many meetings about our missiles,” Khatibzadeh said, mentioning Iran’s ballistic missile program. “With these actions, we become more determined to make our defense shield more active.”

With the start of a new round of nuclear talks in Vienna, Israeli leaders have become increasingly outspoken in their criticism, warning against a return to the 2015 deal and reviving threats to attack Iran if necessary. Israeli media have quoted anonymous Israeli officials talking of tensions in relations with the Biden administration and questioning the U.S. readiness to use force if diplomacy fails.

In Jerusalem, Israel’s foreign minister, Yair Lapid, played down such reports, saying there is no “daylight” between Israel and the United States.

“The common goal is to make sure Iran does not become a threshold nuclear country,” he told The Associated Press at a news conference. “We believe so. The American administration believes so. We have a very constructive discussion with them about this. That will continue.”

“Rest assured that the dialogue we have with President Biden, with Secretary Blinken is positive, is constructive and is aimed at the same goal,” he said.

Talks over Iran’s program in Vienna broke up last week after Tehran offered new demands. Khatibzadeh insisted Iran wasn’t after a “temporary” agreement from the negotiations, which he described as resuming “later this week.” European officials have yet to announce a time for the talks to restart.

In Germany, a party to the nuclear deal, a Foreign Ministry spokeswoman offered unusually blunt criticism of Iran’s actions at the recent round of talks in Vienna.

“Iran is breaking with almost all of the difficult compromises that were previously agreed upon during several months of hard negotiations,” spokeswoman Andrea Sasse said. “In our view, this basis, combined with continued development of Iran’s nuclear program, is not a basis on which the talks can be brought to a promising conclusion.”

Sasse urged Iran to return to the talks with “realistic proposals.”

However, Iranian Foreign Minister Hossein Amirabdollahian separately insisted that Tehran had gone into negotiations in Vienna with “seriousness and good will.”

“We will seek no Plan B simultaneously as we negotiate,” he told journalists. “We will wait and try to make progress in lifting the sanctions as desired by the nation through solid and powerful negotiations.”

AP