A plan to create the world’s biggest artifical reef by sinking a historic cruise liner that frequently came to Southampton has been cast into doubt.  

The iconic SS United States is planned to be submerged off the Okaloosa County coast in Florida where it would create the world’s largest artificial coral reef.

Since 1996, the United States has been rusting on the banks of the Delaware River waterfront in Philadelphia at pier 82.

After a years-long legal debate over its future, plans finally looked set to become a reality when the SS United States Conservancy, which previously owned the vessel, sold the ship to Okaloosa County in September.

However, US Coastguard documents now state the ship might not be fit to make the trip from Philadelphia.

A Captain of the Port Order issued by US Coastguard Captain, Kate Higgins-Bloom, states Okaloosa County, Florida, failed to provide sufficient information in its initial tow plan for the SS United States.

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Okaloosa County’s original plans would have seen the ship moved from the banks of the Delaware River in Philadelphia to Alabama

The Coastguard conducted an assessment of the ship when it was due to be moved to Alabama in November and found the vessel "may not have suitable stability for the intended transit and presents a hazardous condition to the port and waterway."

Requirements have now been set by the US Coastguard – which if Okaloosa County do not meet, will result in a $114,630 fine each day the ship is in violation.

These conditions includes a report prepared by an experienced company, assessing the ship's structural condition as well as other conditions.

For 17 years the liner powered through the Atlantic making constant journeys between Southampton and New York, and was met crowds of almost 70,000 when she first came to Hampshire in 1952.

The SS United States was also the fastest ship in the world at the time.

A spokesperson for owners Okaloosa County said: "Okaloosa County continues to work in close collaboration with the U.S. Coast Guard to ensure a safe move of the vessel from Philadelphia, Pennsylvania to Mobile, Alabama.

"That includes complying with the requests included in the Captain of the Port Order.

"Okaloosa County is confident in the ship’s ability to complete a safe move and future deployment as the World’s Artificial Reef that will be located in the Gulf of Mexico near Destin-Fort Walton Beach, Florida.

"As we work with local, state and federal agencies, we are all in agreement that we should take the appropriate steps to make sure she is moved safely and we are actively taking those steps right now."