Beijing will continue to deepen its relations with Tehran and safeguard mutual interests, after a helicopter crash that killed President Ebrahim Raisi and his foreign minister, Wang Yi, China’s foreign minister said on Tuesday.

“Regardless of how conditions change, Beijing will continue to deepen its strategic partnership with Tehran, safeguard the shared interests of both countries, and continue its efforts for peace in the region and the world,” Wang Yi told Mahdi Safari, Iran’s deputy foreign minister.

China and Iran say they are “strategic allies” with close diplomatic and economic ties. Tehran, which openly declares its enmity with the United States and Europe has built its foreign policy on the basis of close ties with Russia and China.

Expressing condolences on the deaths of Raisi and foreign minister Hossein Amir-Abdollahian the Chinese diplomat said, “In this incident, Iran lost prominent leaders, and China lost good friends and partners.”

China is the main byer of Iran’s crude oil despite US sanctions that prohibit third parties in importing Iranian oil. Estimates indicate Beijing is buying more than a million barrels per day of discounted crude from Tehran, providing billions of dollars to the sanctioned country which is in desperate need of foreign currency.

The United States, the European Union and NATO also expressed official condolences to the Islamic Republic on Monday, prompting strong criticism from some Western politicians and human rights defenders who pointed to Raisi record as a top rights violator who was known as the “Hanging Judge”.