Really it is down to Russia and the United States for capability to do this and Russia has the exact coordinates while the United States I fear wouldn't be meddling in this situation and Ukrainian forces are way too tied up and not prepared for an operation like this in the deep sea.
Technology wise it would be really hard for the United States to deploy underwater assets that would be needed to sabotage the pipeline however very close to this incident zone is the main Russian base....
RE: You never heared of sudden pipeline death syndrome? A declaration of war