Iranian President Hassan Rouhani said on Tuesday that nations responsible for the downward spiral of oil prices will suffer.

“If Iran suffers from the drop in oil prices, know that other oil-producing countries such as Saudi Arabia and Kuwait will suffer more than Iran, said Rouhani. “Those that have planned to decrease the prices against other countries will regret this decision.”

The U.S. shale oil and fracking boom has sparked competition with OPEC, creating downward price pressure as OPEC has refused to cut production in an effort to stave off the threat from shale oil.

Last month, Saudi Oil Minister Ali al-Naimi, largely considered the energy industry’s most powerful player, said OPEC producers will not cut production even if prices fall to $20 a barrel. He added that the days of $100-a-barrel oil may be gone forever.

According to Reuters, in 2013, one-third of Iran’s budget was based on oil sales, and 60% of its exports are tied to oil. “Oil accounted for roughly 90 percent of Saudi Arabia’s overall budget income and Kuwait at 92%,” reported Reuters.

On Tuesday morning, oil fell below $45 a barrel for the first time since April 2009.