BELGRADE (Reuters) -Serbia on Thursday signed a landmark agreement with France's Dassault Aviation for the purchase of an undisclosed number of Rafale fighter jets.

The agreement, signed by Serbia's Defence Minister Bratislav Gasic and Dassault Aviation CEO Eric Trappier, also includes the purchase of "accompanying equipment and services," an announcement said.

The acquisition, made during French President Emmanuel Macron's visit to Belgrade, signals a major shift in Serbia's security and political stance, moving away from Russia, its traditional ally and weapons supplier.

This is the single biggest weapons deal since Serbia became independent from its state union with Montenegro in 2006.

Belgrade curtailed military cooperation with Moscow after Russia invaded Ukraine and it has condemned the invasion, but unlike the EU, which it wants to join, and other Western countries, it has not imposed sanctions on Moscow. 

Serbia's military and air force are loosely based on Soviet technology, but it has also purchased helicopters and transport planes from Airbus, radars from Thales and France's Mistral surface-to-air missiles.

Serbia also operates Chinese missiles and drones. Its defence budget amounts to around 2% of gross domestic product (GDP).

This is Macron's second meeting with Vucic this year and follows the visit of Chinese President Xi Jinping to Belgrade in May, highlighting Serbia's strategic position on the edge of the EU, with ties to the east and west.

The EU remains Serbia's single biggest investor and hundreds of thousands of Serbs work in Western-owned companies. 

But Belgrade, which seeks to diversify its gas supplies, is also dependent on Russian gas and has the Kremlin's support in its opposition to the 2008 independence of Kosovo.

Before it joins the EU, Serbia would have to improve democracy, the rule of law and judiciary, root out corruption, red tape and organised crime and mend ties with Kosovo.

It must also align its foreign policies with those of Brussels, including the introduction of sanctions against Russia.

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