When questioned on Thursday about Russia's plan B to identify the cause behind the Nord Stream terrorist attacks in case the investigation goes awry, Russian Deputy Foreign Minister Sergey Vershinin asserted that his country is "considering all options."

A day before, Vershinin stated that Moscow maintains its stance on conducting an international probe into the recent explosions that targeted the Nord Stream gas pipelines, adding that it was critical for both Russia and Germany to be involved in the process. 

On September 26, three pipelines in the Nord Stream network that runs under the Baltic Sea from Russia to Germany recorded a rapid gas pressure drop and leakage, and three days later, the Swedish Coast Guard declared a fourth gas leak on the damaged pipelines. Sweden, Germany, and Denmark have announced their beliefs that the incidents are the works of sabotage, but the Russian Prosecutor General's Office has labeled the pipeline incidents as acts of international terrorism.

The pipeline operator, Nord Stream AG, said that giving an estimated timeframe for the repair would be impossible.

Russia exclusion puts the credibility of EU probe at risk: Expert

"Russia must be involved in the investigation, as its main energy company, Gazprom, is co-owner of the Nord Stream 1 and 2 installations. Without Russia, the conclusions would not have any validity," Samuele Furfari, professor of the geopolitics of energy at Brussels university ULB, told Sputnik.

This comes after Russian Permanent Representative to the United Nations Vasily Nebenzya said at a UN Security Council meeting on October 1 that Russia "will certainly establish all those involved in this act of sabotage. Any international investigation into what happened can claim impartiality only if Russia takes part in it."

In the same context, Kremlin Spokesperson Dmitry Peskov expressed Russia's concern on Wednesday regarding the recent news conferences in Sweden and Denmark as they suggested Russia's exclusion from the Nord Stream probe. Peskov rejected Western accusations of Russia being the perpetrator as "absurd", while President Vladimir Putin pointed at the US and the UK as the possible culprits. 

Furfari suggested that the UK being a powerful ally of Germany and the prime beneficiary of cheap Russian gas might have done the damage to prevent Russia from tempting Germany into reopening the taps during the upcoming winter. 

"Europe is still faced with the stressing problem of replacing 170 billion cubic meters of gas that Russia was delivering through Nord Stream 1. And the EU still does not know how it could be replaced immediately. It would take years to build the ships to transport LNG and the LNG terminals to replace Russian gas," Furfari concluded.