Spain's threat to press ahead with a demand for $1bn compensation from the London Steam-Ship Owners' Mutual Insurance Association over the Prestige spill has led to a call for consistency in the way international conventions are applied.

The International Group (IG), the organisation linking the 13 leading protection-and-indemnity (P&I) clubs, is joining forces with the International Chamber of Shipping (ICS)  to press for more uniformity in turning conventions into national laws and subsequent legal interpretations.