MÁV Rail Tours operated the inaugural freight demonstrator service on the 159km Hungarian section of the upgraded 350km Budapest - Belgrade main line on February 27. The train hauled by one of the operator’s leased Siemens Vectron electric locomotives left the Hungarian capital shortly after midnight, travelling to Kelebia on the Serbia border and returning to Budapest in the early hours. It was followed later that morning by a service from Kazinbarcika to Novi Sad, Serbia, operated by Rail Cargo Hungary and consisting of tank wagons loaded with sodium hydroxide. The train was hauled by one of the company’s two Chinese-built battery-electric locomotives.
The opening of the upgraded main line might now finally end the diversion of cross-border freight services via Szeged, Hungary’s third largest city. However, the start of passenger services continues to be hindered by technical issues, specifically the authorisation of Chinese-supplied signalling equipment that is equivalent to ETCS, with Hungarian authorities now racing to secure approval ahead of a self-imposed deadline of April 12, the date of the next general election in Hungary.
China provided a loan to cover 85% of the cost of upgrading the Hungarian section of the line and the country’s supply industry has played a leading role in delivering the project. The project involved rebuilding the entire alignment from Soroksár in Budapest to the Serbian border. Track doubling took place on the complete route apart from between Ferencváros and Kunszentmiklós-Tass, which was already used by Budapest suburban services. The work took four years to complete and was carried out by a Chinese-Hungarian consortium of RM International, China Tiejiuju Engineering & Construction and China Railway Electrification Engineering Group, with Chinese equipment and systems also installed. A separate contract to increase capacity on the 7km Ferencvaros - Soroksár section was awarded to a consortium of V-Híd and China Railway Magyarország in 2022.
Serbian section
Chinese contractors were also responsible for rebuilding the 183km Serbian section. China Civil Engineering and China Railway 11th Bureau were jointly awarded a contract in 2021 to reconstruct the 108km line from Novi Sad via Subotica to Kelebia. Work got underway in 2022 with Serbia’s president, Aleksandar Vučić, officially inaugurating the line on October 3 2025. The same contractors were also responsible for the Belgrade - Novi Sad part of the line, with the 34.5km Belgrade - Stara Pazova section reopening in March 2021, followed by the 40.4km Stara Pazova - Novi Sad section in March 2022.
The rebuilt line would potentially enable the journey time between the Hungarian and Serbian capitals to be cut to 3h 40min. It also increases capacity for freight moving between the Balkans to Central Europe, and in the long-term if other projects are completed, from the port of Piraeus in Greece, which is owned by Chinese interests, to Budapest, a regional distribution hub.
The line in Serbia links Belgrade with the major towns of Novi Sad and Subotica and has been rebuilt to accommodate more frequent passenger services operating at up to 200km/h, with the journey time between Belgrade and Subotica cut to 1h 20min compared with 4h 35min previously. Track doubling was carried out on 148km of the line and all level crossings have been removed, with more than 120 structures built to remove conflicts with road traffic, pedestrians and cyclists including five tunnels, 15 underpasses and 27 overpasses.
In contrast, the alignment in Hungary, while more direct, passes mostly through sparsely-inhabited areas with the largest town, Kiskunhalas, having a population of less than 27,000. The maximum speed is limited to 160km/h and the line still has nearly 100 level crossings, which helped to reduce construction costs, reflecting the poor business case for passenger services on the route. However, the existence of these crossings means that an alternative authorisation process is required for ETCS on this section. This is expected to take two months to complete and only recently got underway. As a result, freight operations on the line are currently restricted to 100km/h, and just 40km/h in limited visibility.
ETCS
China Railway Signal & Communication delivered the CTCS Level 3 signalling system for the line, which is equivalent to ETCS Level 2. Testing has been underway since August 2025. The line is also equipped with a centralised traffic control (CTC) system. However, track circuits for Hungary’s nation EVM automatic train protection (ATP) system have not been installed on the line, preventing diesel locomotives and DMUs operated by MÁV Passenger, none of which are equipped with ETCS, from using the line. Hungary’s Ministry of Construction and Transport (ÉKM) confirmed that shunting locomotives and trains from connecting lines such as the Baja - Kiskunfélyegháza - Kecskemét passenger services that need to cross the Budapest - Kelebia line and reverse at Kiskunhalas may operate into the required stations and over spurs without onboard ETCS.
Further restrictions on cross-border operation arise from differing standards for electric rolling stock. In Hungary, pantographs with contact strips up to 1950mm in length are permitted. However, this contrasts with Serbia where the maximum strip size is 1600mm, preventing cross-border operation of some locomotives.
In addition, CRRC-built Soko EMUs, which Serbian Railways (ZS) plans to operate between Belgrade and Budapest, require separate authorisation to operate in Hungary to that already secured to use ETCS installed in Serbia, casting doubt on whether these services will commence next month as planned.
MÁV Passenger currently plans to operate locomotive-hauled international services on the line, which will continue to Vienna. Future passport checks are expected to be conducted at Kelebia, which will delay these EuroCity trains by up to 30 minutes, but studies are underway to determine whether these checks could be performed en-route, which could reduce the Budapest - Belgrade journey time to three hours.
For domestic services MÁV Passenger envisages three tiers of offer using both locomotive-hauled trains and Stadler Flirt EMUs on the Budapest - Kelebia section. Existing suburban trains from Budapest Keketi to Kunszentmiklós-Tass will be supplemented by an express and an all-stations InterRégió service alternating each hour from Keleti to Kiskunhalas and Kelebia. These will offer time savings of up to 1h 44min between Budapest and Kelebia on international services and 47 minutes on stopping services.
Flagship?
The Budapest - Belgrade project is a flagship for the Chinese industry as it continues efforts to break into the lucrative European market. Once approved, it will be the first fully authorised ETCS project delivered by a Chinese supplier in the European Union and could pave the way for more projects. Indeed, the Belgrade - Novi Sad project was regularly cited by China Railway (CR) as an example of Chinese export prowess during the UIC High Speed World Congress held in Beijing in July 2025. Speakers even argued that the speed threshold required to meet the UIC’s principal definition of high-speed rail should be lowered from 250km/h to 200km/h to accommodate the project.
Yet the interoperability and certification issues emphasise the challenges that Chinese suppliers still face when attempting to meet the high technical standards required in Europe. The cost of the Hungarian section of the project, estimated at Forints 1 trillion ($US 3.03bn) - more than the estimated $US 2bn cost of the Serbian section - and the fact that contract values will be kept secret for 12 years by order of the government, also reveals another challenge raised by competing for and delivering major European projects in markets where greater transparency will be required.
