The Biden administration on Friday evening notified Congress that it is waiving nonproliferation sanctions on Iran to allow Rosatom—Russia’s State Nuclear Energy Corporation—to profit without facing U.S. sanctions.

The waivers roll back former President Donald Trump’s sanctions on the Islamic Republic and permit Iran to cooperate with Russia at Iranian nuclear enrichment facilities.

Senior congressional sources say that the Biden administration is quietly renewing the sanctions waivers amid renewed concerns about the budding Tehran-Moscow military alliance. Critics charge that the administration is allowing Iran to develop its nuclear program while enriching Russia through business with state-controlled organizations.

“The Biden administration is pathologically obsessed with reentering a nuclear deal with Iran,” tweeted Sen. Ted Cruz (R-Texas). “They’re so obsessed they’re implementing parts of the last catastrophic deal, even without a new agreement.”

Cruz has been working on legislation that would anchor this particular Trump sanction in law and will be moving forward with a bill designed to force President Joe Biden to reverse his presidential order.