Omani Foreign Minister Yousef Bin Alawi said he is optimistic that an agreement between Saudi Arabia and the Houthi rebels could be reached to end the four-year-war in Yemen.

“There are consultations, there’s mediation and the desire to solve the conflict,” Bin Alawi told Oman’s state television after meeting with the Secretary of State Mike Pompeo in Washington today. ‘’Houthi leaders’ principle is to take the path of peace, security and stability, and I believe they will positively cooperate.”

Pompeo and Bin Alawi agreed that only a political solution will bring an end to the conflict and ensure peace, prosperity and security in Yemen, the State Department said in a statement.

The U.S. has begun efforts to find a negotiated settlement to the conflict, which has triggered the world’s worst humanitarian crisis with tens of thousands killed and millions left hungry and displaced.

In September, devastating attacks on Saudi oil infrastructure highlighted the danger the Yemen conflict poses to regional stability. The strikes were claimed by the Houthis but Saudi officials and observers saw the hand of Iran, which is pushing back against a U.S.-led economic offensive to weaken the Islamic Republic.