The United States is likely to tighten the sanction enforcement on Iran’s crude oil exports over the Hamas-Israel war and the Iranian backing of Hamas, Helima Croft, the head of global commodity strategy at RBC Capital Markets, told CNBC on Wednesday.

“The Biden administration is desperate to contain this war, they clearly do not want it spilling beyond Gaza,” Croft told CNBC’s Dan Murphy on the sidelines of an investment forum in Saudi Arabia on Wednesday.

On Tuesday, U.S. President Joe Biden spoke with Saudi Arabia’s Crown Prince and Prime Minister, Mohamed bin Salman, and “discussed ongoing diplomatic and military efforts to deter state and non-state actors from widening the conflict between Israel and Hamas,” the White House said.

According to RBC’s Croft, “we just don’t know what the red lines are for a number of players in this conflict.”