According to IRNA, citing Tass news agency, Putin expressed his sorrow on Tuesday night, while meeting with Russian Duma Speaker Vyacheslav Volodin, who will travel to Tehran on Wednesday morning to attend the funeral ceremony of President Raisi.

In the meeting, Putin asked the speaker to convey his condolences to the Supreme Leader of the Islamic Revolution and inform him that Russia hopes the continuation and development of bilateral relations in the same way as it is now.

The Russian President also stated that Ayatollah Raisi was a very reliable partner and “if we agreed on something with him, we could always be sure that those agreements would be fulfilled.”

In a message a day earlier, the Russian President called Raisi a true friend who made serious efforts to develop the level of strategic cooperation between Moscow and Tehran.

Meanwhile, Putin also announced Russia's readiness to help Iran investigate the causes of the copter crash that left President Raisi and an accompanying delegation dead.

According to IRNA, a parliamentary source in Russia on the condition of anonymity said that the head of the State Duma will also be present at a ceremony, which will be held in Mashhad, following a funeral service in Tehran.