Millions are being earned by Serbian companies in exports to Russia, according to RFE:

As Radio Free Europe announced on Wednesday, millions are being earned by a number of Serbian companies exporting goods to Russia, bypassing Western sanctions.
According to data to which RFE has access, more than 14,000 shipments of various goods to Russia were registered after the beginning of the war in Ukraine. This showed that goods worth millions of dollars that were on the list of productions covered by the US and European Union sanctions were shipped via Serbian companies.
RFE announced that goods worth more than 140 million dollars had been exported by the Belgrade-based Kominvex alone since the war in Ukraine began. The radio added that about a third were electronic components which could have a military use.
Serbia is recalled not to have aligned with the sanctions policies against Russia.
As RFE said, state of the art technology products, including the US INTEL and AMD, were used to be shipped by Serbian companies. Serbian companies re-exported goods from countries in eastern Asia to Russian companies which are under sanctions individually as part of the supply chain to the Russian military industry.
The Serbian government and Ministries of Internal Affairs and Foreign Trade was said not to have responded to requests for comments and the Customs Authority is said to be refusing to release data on exports claiming it is protecting confidential company information.

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