Russia has announced it will end the sales ban on the S-300 air defense missile system to Iran, following the agreement between the Middle Eastern nation and Western powers.

The decision has raised worry in the West and Israel over Iran's assertiveness.

On Monday, Russia announced it was ending its five-year ban preventing the sale of the advanced S-300 missile defense system to Iran, according to The Associated Press. The announcement comes just a week after Western powers and Iran reached an agreement on the latter's nuclear program.

Russia originally sold the missile system to Iran in 2007 at the price of $800 million; however, pressure from the West led to a ban on the sale in 2010. President Vladimir Putin argued now that if Iran and the West have reached an agreement, the sale could go forward. The missiles could be shipped to Iran at any time.

"The S-300 is exclusively a defensive weapon, which can't serve offensive purposes and will not jeopardize the security of any country, including, of course, Israel," said Russian Foreign Minister Sergei Lavrov.

U.S. Secretary John Kerry called Minister Lavrov asking his country to reconsider the sale. In a press conference, State Department acting spokesperson Marie Harf said the department was concerned.

"We don't believe it's constructive at this time for Russia to move forward with this, but we've worked very closely with the Russians on the P5+1 negotiations," she said, referencing Russia's role in the nuclear negotiations. "We don't think this will have an impact on unity in terms of inside the negotiating room."

Israel has also expressed concern over the sale, despite Russia's assurances, according to CNN.

"Even as Iran disavows article after article in the framework agreement that was announced last week, the international community is beginning to ease restrictions on it," Intelligence Minister Yuval Steinitz said in a statement. "This is the direct result of the legitimacy that Iran is receiving from the nuclear deal being made with it."

Although the missiles cannot be used offensively, their 125-mile range and 16-mile maximum altitude with the ability to hit multiple targets simultaneously could prove a strong deterrent against potential Israeli or Western airstrikes against Iran, explains the Washington Post. The missiles can also be fired off trucks.

However, this is not the only deal agreed by the two nations. Reuters reports Russia and Iran have made a deal to exchange grain and building materials for oil, though companies have not confirmed any sales as of yet.