Hungarian Prime Minister Viktor Orban has convened an emergency meeting of the National Defence Council after explosives were found near a pipeline that transports Russian gas to Hungary.

The discovery in a border area of neighbouring Serbia comes as Orban's party is badly trailing in opinion polls ahead of crucial elections next Sunday.

Opposition leader Peter Magyar accused him of panic-mongering orchestrated by Russian advisers, days after security experts warned of a possible false flag operation that could be blamed on Ukraine.

Orban, an ally of Russian President Vladimir Putin, has resisted EU calls to abandon Russian energy imports since the full-scale invasion of Ukraine.

In recent weeks, Hungarian security experts have raised the possibility of a staged operation, either on Hungarian or Serbian territory, intended to arouse enough sympathy for Orban to help his Fidesz party win the election - or to give Orban an excuse to declare an emergency and postpone or cancel the vote.

Serbian President Alexander Vucic, a close ally of Orban, informed the Hungarian leader of the discovery on Sunday morning.

Two rucksacks full of explosives and detonators were found by the Serbian army near the village of Tresnjevac in the Kanjiza district, about 20km (12 miles) from the point where the TurkStream pipeline crosses into Hungary.

Our units found an explosive of devastating power, Vucic said in a post on Instagram. I told PM Orban that we would keep him updated on the investigation.

Hungary receives between five and eight billion cubic metres of Russian gas a year through the TurkStream pipeline, which both Hungary and Slovakia depend on for Russian gas.

Balint Pasztor, president of the Vojvodina Hungarian Association, and another key Orban ally, posted on Facebook: If the investigation proves that we were not the primary target after all, but rather Hungary's supply lines, then this makes it even clearer: the terrorist attack was planned with the aim of bringing down Viktor Orban.

Fidesz has made hostility to Ukraine a cornerstone of its election campaign.

At election rallies, Orban has told supporters that low heating and fuel prices in Hungary are only possible thanks to cheap Russian oil and gas, both of which arrive in Hungary by pipeline - oil through Ukraine, and gas through the Balkans.

Orban alleges that a Kyiv-Brussels-Berlin axis is conspiring to stop Hungary from getting cheap Russian fuel, aiming to impose their puppet prime minister Magyar in the upcoming election. A Tisza government, Orban claims, could also drag Hungary into a European war against Russia.

Orban has already accused Ukrainian president Volodymyr Zelensky of imposing an oil blockade on Hungary, as no Russian oil has arrived through the Druzhba pipeline, which crosses Ukrainian territory, since the end of January.

Ukraine asserts that the pipeline was damaged in a Russian attack, and should be functional again by mid-April.

There have been no official allegations of Ukrainian involvement in the pipeline incident so far. However, a well-informed Serbian source indicated to the BBC that allegations could surface as early as Monday, when Serbian authorities are expected to release the first results of their investigation.

The Ukrainian government has pre-empted any accusations of involvement, denying any connection to the incident. Most likely, it’s a Russian false-flag operation aimed at intervening in Hungarian elections, stated foreign ministry spokesman Heorhiy Tykhyy.

As the election nears, Hungarian political dynamics remain charged, with ongoing accusations and warnings about potential manipulations defining the landscape.