 However, the adoption of the United Nations Convention on the Law of the Sea (UNCLOS) has prescribed a process which prompted several countries to submit claims or to reinforce pre-existing claims to portions of the seabed of the polar region.As defined by the UNCLOS, states have ten years from the date of ratification to make claims to an extended continental shelf.They must present to the Commission on the Limits of the Continental Shelf, a UN body, geological evidence that their shelf effectively extends beyond the 200 nautical miles limit.