Veteran US investigative journalist and Pulitzer Prize winner Seymour Hersh, who revealed in February that the United States was behind the operation to blow up three of the four Nord Stream gas pipelines last September, claimed last week that the White House is now attempting a "cover-up" of the sabotage by feeding false alternative narratives to the media.

He was referring to a story run by The New York Times early this month, which alleged that "a pro-Ukrainian group carried out the attack". The information "originated with a group of CIA experts in deception and propaganda whose mission was to feed the newspaper a cover story", Hersh wrote. "The disinformation professionals inside the CIA understand that a propaganda gambit can only work if those on the receiving end are desperate for a story that can diminish or displace an unwanted truth".

The displacement gambit being offered — that a team of six people using a rented yacht were responsible for the pipeline explosions — has failed to convince experts, who say the sabotage could only have been carried out at the state level.

Initial probes by Swedish and Danish investigators suggest that the blasts were equivalent to "several hundred kilos of explosives", which damaged the pipelines up to 100 meters under the Baltic Sea, setting off an environmental nightmare as half a million metric tons of methane was leaked.

Danish seismic monitoring equipment on the island of Bornholm detected the equivalent of a 500 kilogram TNT explosion in the sabotage event that destroyed both pipes of the Nord Stream 1 pipeline and one of the Nord Stream 2 pipelines.

The alternative rent-a-yacht scenario prompted Jan Oberg, director of the Transnational Foundation for Peace and Future Research, to call the narrative "dumb, improbable and unlikely".

It is interesting to note that while Washington has rejected Hersh's detailed revelation as "utterly false and complete fiction", pointing to it being based on anonymous sourcing, it has yet to say anything negative about The New York Times' account of the attack, even though it quotes unnamed US officials denying any US government involvement.

Given the attack was on transnational infrastructure and the substantial and worrisome environmental consequences from the blasts, in terms of both the greenhouse gas emissions and the disturbance of heavy metal contaminants in the seabed sediment, it is both necessary and urgent that an independent, impartial, objective and transparent investigation be conducted as soon as possible under the auspices of the United Nations, with broad participation by international experts to determine the culprits.

The deliberate sabotaging of transboundary infrastructure by any party amounts to an act of international terrorism that must be dealt with collectively by the international community.