Abdel Malek El Houthi, the leader of the Houthi militant group in Yemen, warned of possible attacks against Saudi Arabian oil tankers if the coalition backing the Yemeni government attacks the port of Hodeidah, Reuters reports.

He also threatened Saudi Arabia and the UAE with ballistic missiles, according to Reuters.

Saudi Arabia and the UAE are battling the Houthis in an attempt to restore the internationally recognized government of President Abd Rabbu Mansour Hadi. He was forced to flee abroad in 2015 as the Houthis extended their control across the country and tried to monopolize power in Sana’a, BBC reports.

Hodeidah is Yemen’s largest port and is under the control of the Houthi militants. It is located on the Red Sea close to the commercially important Bab El Mandeb Strait.