BELGRADE (Reuters) - Aleksandar Vulin, the pro-Russian head of Serbia's Security and Information Agency (BIA) resigned on Friday after being sanctioned by the United States in July.
The U.S. accused Vulin of helping Moscow in its "malign" activities, and with having links to an arms dealer and a drug trafficking ring.
In his resignation letter, Vulin who is also to head of the co-ruling Movement of Socialists, said he was resigning to remove the danger of Western "threats and blackmails" to President Aleksandar Vucic and Serbia over joining international sanctions against Russia.
"If we would agree to that, the next demand would be ... the acceptance of Western values," Vulin said.
"I will not allow myself to be the cause of blackmail and pressure on Serbia and the Serbian world. That is why I submit my irrevocable resignation," he said.
Vulin, who previously served as the defence minister and the minister of interior, is the first Serbian high-ranking official who has been sanctioned by the U.S. since Vucic took presidential office in Serbia in 2017.
The Serbian government and the BIA could not be immediately reached for comment.
In July, Vucic said Serbia would investigate the accusations made by the United States.
Vulin's resignation comes as Serbia is under pressure by the West to mend ties with independent Kosovo, its former Albanian southern province. It also comes only two days after Vucic called a snap election for Dec. 17.
Although Belgrade has repeatedly condemned Russia's invasion of Ukraine, it has so far refused to join international sanctions against Moscow.
Serbia is a candidate to join the European Union, but it must first root out corruption, organised crime and align its foreign policies with those of the bloc.