Syrian regime leader Bashar Assad met with Iran's Supreme Leader Ayatollah Ali Khamenei during an unannounced one-day visit to Tehran on Sunday, according to local media.

It was Assad's second official visit to Iran since Syria’s civil war erupted in 2011. His last visit was in February 2019.

Sunday’s meeting was also attended by Iran's President Ebrahim Raisi and Foreign Minister Hossein Amir-Abdollahian.

Khamenei said in statements cited by local media that Syria’s "credibility" was "much greater now than in the past" and it was being looked at "as a power" today.

Iran has been one of Assad's strongest regional allies, and has helped his regime with money and weapons during the Syrian conflict.

Khamenei, in his remarks, referred to the role played by the former chief of the Islamic Revolutionary Guard Corps (IRGC)’s Quds Force, the late Gen. Qassem Soleimani, in the Syrian war, saying the connection between Damascus and Tehran should be strengthened further.

Earlier in the day, Assad met with Raisi, during which both sides reviewed bilateral ties and economic cooperation.

Raisi told the visiting Syrian delegation that the future of the region was to be "determined by the resistance of the nations, not on the negotiating table," his office said in a statement.

He also expressed the "serious will" of his country "to enhance economic and trade cooperation" with Syria.

For his part, Assad declared his country's readiness to expand economic cooperation with Iran, the statement added.

According to Nour News, which is close to Iran's top security body, Assad and his accompanying delegation returned to Damascus after their daylong visit to Iran.