Russia has canceled a planned sale of MiG-31 fighter jets to Syria, a Russian newspaper reported Wednesday. Russia had agreed in 2007 to sell Syria eight MiG-31 jets for a total of roughly $450 million.

The MiG-31 is a supersonic fighter plane designed to fly at both high and low altitudes. It is capable of tracking and attacking multiple targets simultaneously, and of tracking targets both below and above the plane.

Sources in Russia's Defense Ministry differed regarding the reason for freezing the sale. While one told the paper that Israel was behind the cancellation of the deal, a second said Syria was simply unable to pay for the fighter planes.

"The Israelis put pressure on Russia, and the contract was annulled,” the first source claimed. Israel has managed to get similar deals canceled in the past, he said.

Israel has openly opposed Russian arms sales to Syria and Iran. In April, Israel offered to sell Russia advanced unmanned aircraft (UAVs) if Russia would agree not to sell the UAVs or anti-aircraft systems to either Iran or Syria.

Russia has announced that it intends to sell the S-300 missile defense system to Iran, a sale Israel strongly opposes. Iran has purchased one advanced missile defense system from Russia, but Russia has not yet delivered the system.