Russian news agencies reported on Tuesday that Russia is honoring its deal with Iran and delivering S-300 surface-to-air missiles that could protect Iran from multiple targets and shoot down other missiles.

Russia and Iran were able to write a contract for their deal after international sanctions on Iran were lifted due to the nuclear deal with the U.S. and its allies. However, BBC New reports that Saudi Arabia, Israel, and the United States are against the new missile contract between Iran and the Kremlin.

According to Russian officials, the first missiles could be delivered 18 months after Iran decides what type of S-300 missiles they want; talks between the two countries continue.

“The deal to supply the S-300 to Iran has not only been signed between the parties but it has already come into force,” said Sergei Chemezov, head of Russia’s Rostec arms firm, speaking at the Dubai Airshow-2015.

The deal was originally signed in 2007, but international sanctions forced Russian leaders to freeze the deal. President Putin unfroze it in April. CBS News reports that the original model of the S-300 that was proposed in the first deal are no longer manufactured, and Russian officials had to modify the agreement.

Israel and the U.S. worry that if Iran receives these missiles they could effectively protect their nuclear sites from airstrikes. CBS News adds that Israel also fears that the Islamic State could get their hands on the S-300 if they are in Iran.