Measures to lessen the threat posed by a sunken Second World War supply ship loaded with explosives have been postponed.

The SS Richard Montgomery sank off the coast of Sheerness in August 1944 with 1400 tons of explosives aboard.

Even though the ship has been sitting in the water for more than 78 years, there is still considered to be a risk that the explosives could detonate, potentially causing a tidal wave that could wreak havoc on the town.

Responsibility for the management of the wreck rests with the Department for Transport (DfT), which has been regularly monitoring the ship’s condition.

In recent years, signs of a deterioration in the ship’s hull have been observed, which it is thought could increase the danger.

Two years ago it was decided that the ship’s three masts – which project above the water line – would be removed, as it is thought that their weight is placing an additional strain on the deck-plating and so crucially on the cargo hold.

A contract was awarded by the Government to safely remove the masts using jack-up rigs placed on the seabed, providing access to each mast via cranes.]

The work was already delayed once after bombs were found lying on the seabed. They were removed last summer.

But preparatory work which included a detailed survey of the wider area around the wreck has now identified another 18 “objects” on the seabed in locations which were required for the cranes.

The DfT has not revealed what the objects are.

But in any case, the new information has meant the government department has had to re-assess the viability of using jack-up rigs.

It has concluded it is not possible to proceed with this approach, because of the potential danger to those working on the project.

There is an exclusion zone around the immediate wreck site, marked by a ring of buoys, but increasingly yachts, jet-ski users and even paddle-boarders have been seen ignoring the exclusion zone and venturing dangerously close.

They risk not only a large fine if caught, but also potentially losing their lives should the wreck chose that moment to blow up.

The SS Richard Montgomery is named after an American hero of their War of Independence against Britain. He died while attacking British Quebec in 1775.

Gordon Henderson, the MP for Sittingbourne and Sheppey, said: “DfT staff remain committed to the removal of the masts, but it will now be necessary to restart the process and identify a new, safer solution for their removal.

“The department is working hard to complete this process as soon as possible, but unfortunately the situation means that work will not take place this year as planned.

“However, the project has already delivered a significant benefit in enhancing our understanding of the wreck site, and this vital information will be used to inform its ongoing management.”