Russian President Vladimir Putin has written to Iran’s new Supreme Leader Mojtaba Khamenei to congratulate him, according to the Kremlin.

“At a time when Iran is confronting armed aggression, your tenure in this high position undoubtedly requires great courage and dedication,” Putin wrote. “We are confident that you will honorably uphold your father’s legacy and unite the Iranian people in the face of severe trials.”

Putin then reiterated Moscow’s “continued support for Tehran and solidarity with our Iranian friends,” while adding that Russia “has been and will remain a reliable partner of the Islamic Republic.”

Iran on Monday named Mojtaba Khamenei to succeed his father Ali Khamenei as Supreme Leader, signaling that hardliners remain firmly in charge in Tehran a week into its conflict with the United States and Israel.

Mojtaba, a mid-ranking cleric with influence inside Iran’s security forces and vast business networks under his father, had been seen as a front-runner in the lead up to the vote by the assembly, a body of 88 clerics charged with choosing the new leader after Ali Khamenei.

“By a decisive vote, the Assembly of Experts, appointed Ayatollah Seyyed Mojtaba Hosseini Khamenei as the third Leader of the sacred system of the Islamic Republic of Iran,” the assembly said in a statement issued just after midnight Tehran time.

The position gives Mojtaba the final say in all matters of state in the Islamic Republic.

Mojtaba’s appointment will likely draw the ire of U.S. President Donald Trump, who said on Sunday that Washington should have a say in the selection. “If he doesn’t get approval from us, he’s not going to last long,” he told ABC News.

Israel, ahead of the announcement, threatened to target whoever was chosen.

Mojtaba’s father, Supreme Leader Ali Khamenei, was killed in one of the first strikes launched against Iran more than a week ago.

- Agencies