Russia on Saturday condemned the U.S.-Israeli strikes on Iran as “a preplanned and unprovoked act of armed aggression against a sovereign and independent U.N. member state,” demanding an immediate halt to the military campaign and a return to diplomacy.

In a statement posted to Telegram, the Foreign Ministry accused Washington and Tel Aviv of “hiding behind” concerns about Iran’s nuclear program while actually pursuing regime change.

It warned the attacks risked triggering a “humanitarian, economic and possibly radiological catastrophe” in the region and accused the U.S. and Israel of “plunging the Middle East into an abyss of uncontrolled escalation.”

Russia has emerged as a key trade partner and supplier of weapons and technologies for Iran, which has faced bruising international sanctions. Though Russia’s Foreign Ministry was quick to condemn the U.S.-Israeli attacks, the Kremlin will likely carefully assess its response following a recent warming of ties between Moscow and Washington.

Russian President Vladimir Putin has praised U.S. President Donald Trump’s efforts to mediate an end to the conflict in Ukraine, and Moscow and Washington have discussed ways to revive their economic ties.

Russian Foreign Minister Sergey Lavrov spoke by phone with Iranian Foreign Minister Abbas Araghchi, Russia’s Foreign Ministry said. Araghchi briefed Lavrov on Iran’s attempts to repel the attacks and said Iran would seek to convene an urgent U.N. Security Council session, it said. Lavrov reiterated Russia’s condemnation of the U.S.-Israeli strikes and Moscow’s readiness to help broker peace.

Kremlin spokesman Dmitry Peskov said Putin discussed the situation in Iran with Russia’s Security Council via videoconference, but did not give details.

In the Foreign Ministry statement, Moscow called the bombing of nuclear facilities under International Atomic Energy Agency safeguards “unacceptable” and said it stood ready to help broker a peaceful resolution, while placing full responsibility for the escalation on the United States and Israel.

“Responsibility for the negative consequences of this manmade crisis, including an unpredictable chain reaction and spiraling violence, lies entirely with them,” the statement said.

Russia’s Foreign Ministry also condemned what it called “the serial nature of destabilizing attacks carried out by the U.S. administration,” accusing the U.S. of attacking “the international legal pillars of the world order.”

Russia has maintained a delicate balancing act in the Middle East for decades, trying to navigate its warm relations with Israel even as it has developed strong economic and military ties with Iran.

Iranian forces and Russian sailors conducted annual drills in the Gulf of Oman and the Indian Ocean last week aimed at “upgrading operational coordination as well as exchange of military experiences,” Iran’s state-run IRNA news agency reported.

Putin and his Iranian counterpart, Masoud Pezeshkian, signed a broad cooperation pact in January last year as their countries deepened their partnership in the face of stinging Western sanctions.

The West alleges that in 2022, Russia and Iran signed a $1.7 billion deal for Shahed drones after Putin sent troops into Ukraine, and the U.S. also believes Iran has transferred short-range ballistic missiles, but neither Moscow nor Tehran ever acknowledged the actions.

Ukrainian President Volodymyr Zelenskyy voiced support for the strikes on Iran, calling it “an accomplice of Putin” for supplying Moscow with Shahed drones and the technology to produce them and other weapons during its four-year war against Ukraine.

Russia and Iran also pooled their efforts to shore up Bashar Assad’s government during Syria’s civil war, but failed to prevent his downfall after a lightning offensive by the opposition. Assad and his family fled to Russia.

Some observers in Moscow argue that the focus on the confrontation between Israel and Iran could distract global attention from the war in Ukraine and play into Russia’s hands by potentially weakening Western support for Kyiv.