Russian Deputy Foreign Minister Sergei Ryabkov warned on Wednesday that direct U.S. military assistance to Israel could radically destabilise the situation in the Middle East, where an air war between Iran and Israel has raged for six days. In separate comments, the head of Russia's SVR foreign intelligence service, Sergei Naryshkin, was quoted as saying that the situation between Iran and Israel was now critical. Ryabkov warned the U.S. against direct military assistance to Israel or even considering such "speculative options," according to Russia's Interfax news agency.