You think someone was bribed to choke up the canal or something? What incentive would you have to do something like that? Is this part of a spy movie?
I don't think that happened but if I did I'd be thinking financial market manipulation for private gain long before intelligence agency shenanigans by states.
I'd imagine a long blockage has an effect on oil prices, as most oil coming from the Gulf States to Europe (and America's west coasts?) would normally travel through there.