Serbia will have to dissolve its new free-trade pact with Russia's Eurasian Economic Union (EEU) when it joins the EU, the European Commission has said.

"A free-trade agreement between Serbia and Russia is in place since 2000. We understand that this agreement is to be extended to the Eurasian Economic Union," an EU spokesperson told EUobserver on Tuesday (27 August).

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Russia launched the Eurasian Economic Union amid some fanfare in 2015 (Photo: kremlin.ru)

"Serbia can enter into agreements with other countries or organisations before the country's EU accession," the spokesperson said.

But "in the context of its EU accession negotiations, Serbia committed to withdrawing from all bilateral free-trade agreements on the day of its accession to the EU," the spokesperson added.

The EU commission clarified Serbia's obligations one day after Russia's ambassador in Belgrade, Alexander Botsan-Kharchenko, announced that Serbia would sign the EEU trade accord on 25 October.

The pact would "give new quality to future cooperation" between Serbia and the Eurasian bloc, Botsan-Kharchenko said after meeting Serb president Aleksandr Vucic.

The Serbian embassy to the EU could not be contacted for comment.

EU foreign ministers might discuss the EEU deal amid other issues when they meet their Western Balkans counterparts in Helsinki later this week.

But the European Parliament echoed the commission line.

"The text of the free trade agreement [with Russia's bloc] should ... include an exit clause, which guarantees that Serbia can retract the agreement by the date of its final accession to the EU," David McAllister, a German centre-right MEP who chairs the EU parliament's foreign affairs committee, also told EUobserver on Tuesday.

McAllister met Vucic in Belgrade the same day the Serbian president held talks with the Russian ambassador.

The MEP and Vucic did not discuss the Eurasian pact, but Vucic reiterated his "support" for "the European path of Serbia" when they spoke.

Serbia began EU accession talks five years ago and aims to join by 2025.

Its historical and cultural ties to Russia go back centuries, however.

Unlike most other EU hopefuls, it does not want to join Nato, buys Russian arms, and boycotts many EU foreign policy decisions, including Europe's monumental Russia sanctions.

Russia created the EEU in 2015 to counter EU expansion.

It includes Armenia, Belarus, Kazakhstan, and Kyrgyzstan.

The Eurasian club has also been mythologised as a fortress of orthodox values by Russian propaganda amid competition for influence in the former Iron Curtain region

"This [the Serbian trade pact] is a significant event," Botsan-Kharchenko, the Russian ambassador, said in previous remarks on the move.

The deal gave Serbia access to an EEU market of 182m people worth $1.9 trillion [€1.7 trillion], he added.

He did not mention that Serbia already has free-trade pacts, which it will also have to dissolve, with Belarus and Kazakhstan as well as Russia, making its EEU gesture even more symbolic.

For its part, the EU is a liberal market of 513m people worth €16.9 trillion in the geopolitical beauty contest.

"The EU remains Serbia's most important trade partner, covering 63 percent of total trade, with very good dynamics of growth. Trade with Russia is less than 10 percent of Serbia's total trade," the EU spokesperson said on Tuesday.

But the number of Serbians who want to join the EU is just 53 percent despite its economic shine, according to a poll by the country's European integration ministry in July.