Gazprom Neft has invested 2.5 billion euro ($2.9 billion) in the development of its Serbian subsidiary NIS [BEL:NIIS] since 2009, the CEO of the Russian oil company, Alexander Dyukov, said.

The investments have allowed NIS to become one of the leaders in the energy sector of Southeast Europe (SEE), Dyukov said in a video file posted on the website of Serbian news agency Tanjug on Monday.

Gazprom Neft plans to continue investing in the development of NIS, Dyukov said during the official ceremony for the launch of the construction of a deep conversion complex (DCC) at the Pancevo refinery of the Serbian company on Monday, according to SeeNews.

The DCC construction represents the second stage of the Pancevo refinery modernisation programme funded by Gazprom Neft. Investment in the construction of DCC will total about 30 million euro and will increase the conversion rate of the refinery to 99.2%, Gazprom Neft said.

Under the first stage of the programme, completed in 2012, Gazprom Neft invested 540 million euro in the construction of a light MHT/DHT hydrocracking and hydrotreating complex, allowing the Pancevo refinery to commence production of Euro-5 fuel.

Gazprom Neft controls a 56.15% stake in the capital of Naftna Industrija Srbije (NIS), while the Serbian government owns a 29.87% shareholding interest.