Russian President Vladimir Putin held an unannounced high-level meeting with Ali Larijani, secretary of Iran's Supreme National Security Council, at the Kremlin presidential palace on Friday. Larijani, a senior advisor to Iran's Supreme Leader Ali Khamenei, was appointed to the post last August and visited Moscow after US airstrikes on Iranian nuclear facilities.

The Kremlin said in a brief statement that "the president received Ali Larijani, secretary of Iran's Supreme National Security Council, who is on a visit to Russia." The statement did not disclose what was discussed between the two leaders. Iran's ambassador to Russia, Kazem Jalali, said later that the meeting focused on bilateral relations and included "consultations on important regional and international issues."

The visit came after the US imposed sanctions on Mr. Larijani earlier this month for allegedly being involved in violently suppressing anti-government protests that have spread across Iran since late December. Iran has portrayed the unrest as a foreign-backed insurgency, saying external agents have armed rioters to provoke a harsh state response and provide a pretext for US intervention.

Mr. Putin discussed the unrest in a phone call with his Iranian counterpart, Masoud Pezeshkian, earlier this month. According to reports, US President Donald Trump came close to ordering punitive strikes against Iran at the height of the protests, although he has delayed a final decision. He has, however, sent a naval fleet to the region to pressure Iran into accepting new demands on the nuclear deal.

US military planning is active, with media reports citing administration sources as saying Mr. Trump is considering options ranging from strikes on Iranian security forces and nuclear facilities to targeting officials, with the aim of reigniting anti-government protests.

After Mr. Trump's warning of a "much worse" attack, Iran has vowed to "defend itself and take retaliatory measures like never before." As both sides prepare for military exercises in the region, warnings of escalation and any potential miscalculation are growing.