Russian President Vladimir Putin has asked Iran's Supreme leader Ayatollah Ali Khamenei for a restrained response to Israel's suspected killing of the leader of Hamas, advising against attacks on Israeli civilians, two senior Iranian sources said, Paralel.Az reports citing Reuters.

The message, according to the sources, was delivered on Monday by Sergei Shoigu, a senior ally of the Kremlin leader, in meetings with top Iranian officials as the Islamic Republic weighs its response to the assassination of Ismail Haniyeh.

Tehran also pressed Moscow for the delivery of Russian made Sukhoi Su-35 fighter jets, the two Iranian sources, privy to the meeting in Tehran, the sources told Reuters.

In Moscow, the Kremlin did not respond to a request for comment. State-run RIA news agency reported on Tuesday that Shoigu said he discussed Haniyeh's killing on his Tehran visit.

The two sources with knowledge of the matter did not provide further details on the talks with Shoigu, who was defence minister before becoming the secretary of Russia's security council in May.

They said Shoigu's visit was one of several avenues Moscow had used to relay to Iran the need for restraint while at the same time condemning Haniyeh's killing as "a very dangerous assassination", in a bid to prevent a Middle East war.

The Middle East, the sources said, was on the brink of a major war and those behind the assassination were clearly trying to trigger such a conflict.

Russia has cultivated closer ties with Iran since the start of its war with Ukraine and has said it is preparing to sign a wide-ranging cooperation agreement with Tehran.