Foreign Minister Sergei Lavrov said Monday that Russia had not yet decided whether it would deliver advanced S-300 missile systems to Syria, but would not make a secret of the matter if it took such a decision, the TASS news agency reported.

Russia's daily Kommersant newspaper, citing unnamed military sources, reported earlier on Monday that Russia might start supplying the anti-aircraft missile systems to Syria in the near future. The Kremlin declined to comment.

Lavrov said Friday that Western military strikes on Syria this month had removed any moral obligation Russia had to withhold the missile systems from its ally Syrian President Bashar al-Assad.

"We'll have to wait to see what specific decisions the Russian leadership and representatives of Syria will take," TASS cited Lavrov as saying on Monday during a visit to Beijing.

"There is probably no secret about this and it can all be announced [if a decision is taken]," added Lavrov.

Kommersant said Monday that experts believed that Israel would react negatively to any decision to supply the missiles and might bomb the area where they would be deployed.

A Russian diplomat who spoke to Reuters on condition of anonymity said Israel has asked Moscow not to supply the Syrian military with the S-300s. An Israeli government spokesman declined to comment.

The state-of-the-art S-300 is capable of engaging up to six targets simultaneously, with two missiles assigned per target to ensure a high kill probability. The missile systems have a range of 200 kilometers (120 miles), which cover the airspace of Lebanon, sometimes used by Israeli planes to strike Syria and Israel itself.

The Assad regime was set to get the missile defense systems in 2013, but Russian President Vladimir Putin froze the deal after talks with EU leaders and Israel. He stressed, however, that Russia would review the decision if the U.S. attacked. In the wake of the missile strikes against the regime, the delivery of the S-300 looks more than likely.

Experts believe that with the S-300s the Assad regime will be in possession of a comprehensive air defense umbrella.

The U.S., the U.K. and France hit the Assad regime in Syria with missile strikes on April 13 in response to a suspected poison gas attack that killed more than 70 civilians. Russian military and the regime said most of the missiles were intercepted, while U.S. President Donald Trump tweeted "mission accomplished" following the strikes.