Syrian regime's tankers carrying out oil trade with the PKK terrorist group's Syrian affiliate, the People's Protection Units (YPG), were targeted by the U.S.-led coalition once again.

According to local sources in Deir el-Zour, coalition forces ambushed the eastern outskirts of the province with hummers, where the regime and YPG were carrying out oil trade.

Simultaneously, coalition jets hit three oil-laden tankers, which left from the al-Shuail town that were bound for the other side of the Euphrates. Four people were reportedly killed in the airstrikes.

The coalition has not released any statement regarding the incident yet.

The Bashar Assad regime, struggling with recent shortages, reached a deal with the YPG to buy crude oil, reports suggested earlier this week. As part of the agreement, the YPG would sell oil extracted from Tanak, one of Syria's largest oil fields near the Iraqi border, at a price of $41 a barrel. About 70% of Syria's oil resources lie within the territories currently occupied by the U.S.-backed YPG, in the eastern and southern parts of the country. The terrorist organization holds the eastern part of Deir el-Zour, one of Syria's largest energy sources. There are 11 large oil fields on the eastern side of the Euphrates, which cut the province in two. These oil fields make up around one-third of Syria's energy resources.

This was the second time the coalition targeted the oil trade between the regime and YPG, after an attack in May. Previously, the coalition forces targeted the regime's oil tankers, which were transporting their cargo on the Euphrates River, with heavy machine guns. They later seized the tankers. The incident came after civilian protests against the YPG's arbitrary usage and sale of Deir el-Zour's oil resources. In April, a gasoline crisis broke out in the regime-held areas. In the provinces of Damascus, Aleppo, Latakia and Tartus, there were long lines of cars waiting in front of gas stations.

The YPG has been carrying out negotiations with the Bashar Assad regime since 2017 about the occupied oil fields. In July 2017, the YPG handed over control of oil production in the Rimelan region to the regime following a revenue-sharing deal between both sides.

Also, in February, the YPG agreed on a deal with the regime to transfer oil extracted from occupied areas to the regime-dominated areas in Deir el-Zour. According to the agreement, regime-affiliated companies, operating west of Deir el-Zour, were expected to lay pipes under the Euphrates to transport oil to the war-torn country's eastern provinces. The agreement aimed for a rapid transfer of oil, which was previously carried by boats.