THE wreck of ill-fated Southampton liner Titanic is a step closer to becoming an official international maritime memorial to the passengers who perished in the tragic sinking.

The underwater grave for many of the 1,503 victims, 549 of whom were from Southampton, will be protected from relic hunters under legislation being considered by the United States Congress this week.

It has taken 22 years since the Titanic was discovered, 12,000ft down on the North Atlantic seabed, for the historic site to be protected by law.

The liner sank on April 15, 1912, during its maiden voyage from Southampton to New York after hitting an iceberg.

If the proposed bill is approved, the US will join Britain in ratifying an international treaty struck more than a decade ago with Canada and France.

Britain has already endorsed the treaty. It requires two nations to bring its principal terms into force for all four countries.

The treaty would regulate visits to the site, located in international waters 225 miles off the coast of Newfoundland, Canada. The agreement came at the urging of the wreck's discoverer, undersea explorer Robert Ballard.

He said salvagers and tourism visits had caused the wreck to deteriorate.

The move is opposed by Premier Exhibitions Inc, the US company which obtained salvage rights to the wreck.

British Titanic Society secretary Steve Rigby, who visited Titanic in 2001, said tourist trips to the sea floor should not be stopped.

"It was an amazing and emotional experience, I cried for about three minutes," he said.

"Providing you don't touch the wreck, I believe it does no damage."