Earlier, deliveries were planned to be completed in 2017, but both sides seem to have decided to speed things up.
The S-300 is extremely significant for Tehran. The potent defensive surface-to-air missile (SAM) system serves as a "major guarantee that no one will attack Iran, be it Israel, NATO or Saudi Arabia," the publication noted.
It is the latter that worries Iran, not the former. "An assault launched by Israel or any other Western power seemed almost inevitable in, say, 2013, but after anti-Iranian sanctions were lifted last winter this appears to be an unlikely scenario," the media outlet explained.
Meanwhile, Iran's rivalry with its archenemy, Saudi Arabia, has been escalating since world powers and Tehran inked the nuclear deal.
"The oil kingdom has already shown that it is ready to carry out a military operation [beyond its borders] by launching an offensive in Yemen. This is why Iran's wish to receive the [S-300] systems as soon as possible, before the end of the year, is understandable," the media outlet explained.
Russia will also benefit from this delivery schedule. Not only will a major arms deal be completed. For Moscow, it will also mean that a years-long dispute over the deal will become a thing of the past.
Russian President Vladimir Putin lifted the S-300 delivery ban in April 2015, shortly after the P5+1 group of international negotiators and Iran reached a framework nuclear agreement to remove all economic sanctions against Tehran in exchange for its pledge to ensure that all nuclear research in the country will be for peaceful purposes.
Russia delivered the first S-300 battalion earlier this year.