Nearly 20,000 tonnes of "potentially explosive" cargo should be dumped at sea, a senior councillor has said, as anger mounts over the handling of a damaged ship docked in a Norfolk port.

The MV Ruby remains berthed in Great Yarmouth harbour, despite other nations turning the vessel away.

It arrived there last month loaded with ammonium nitrate - a form of fertiliser which can be explosive - after it suffered storm damage.

Last Saturday, the vessel put to sea again and dumped 300 tonnes of the cargo in the North Sea about ten miles off the town's beaches.

The dumped material had become contaminated with fuel oil and seawater as a result of the damage.The MV Ruby docked in Great Yarmouth portThe MV Ruby docked in Great Yarmouth port (Image: Luke Martin Photography)

Afterwards, the ship returned to Yarmouth, to the fury of Graham Plant, the borough council’s deputy leader.

He has questioned whether the entire cargo should be dumped at sea to put an end to the saga.

It comes as the latest update suggests it could be 40 days before the cargo can be safely transferred to another vessel.

Mr Plant said: "We are playing Russian roulette and we do not know if the cargo is safe or not until it has all been inspected for contamination.

"I do not want that in my port and town where my kids and grandchildren live without having confidence it is been handled competently.

"If it is safe to dump at sea, which is what they are telling us, why not dump the rest of it?

"We are talking about the wellbeing of people in Great Yarmouth."

Graham Plant, deputy leader of Great Yarmouth Borough CouncilGraham Plant, deputy leader of Great Yarmouth Borough Council (Image: Newsquest)

Peel Ports, which owns Great Yarmouth Port, insists it has done the right thing in allowing the MV Ruby to dock, saying it has the capability to handle hazardous materials.

It says it is working with the Department for Transport, the Health and Safety Executive (HSE) and the Maritime Coastguard Agency (MCGA) to ensure the situation is being handled correctly.

Richard Goffin, director or Peel PortsRichard Goffin, director or Peel Ports (Image: Newsquest)

All non-essential port operations have been halted to "mitigate any risks," the MCGA has said.

While ammonium nitrate is generally considered safe to transport, contamination with diesel fuel can increase the chance of an explosion if ignited.

"Why would we welcome this into a British port, it is ridiculous," Mr Plant said.

Before her arrival in Great Yarmouth on October 28, the ship had been anchored about 11 miles off the coast of Margate in Kent while awaiting repairs to her hull and propeller.

The Maltese-registered boat had initially set off from the northern Russian port of Kandalaksha in July and was supposed to be taking her cargo to Africa before becoming damaged.

Both Swedish and Lithuanian authorities refused to allow it to enter their waters, according to reports.

Fears were raised when it was revealed that MV Ruby was carrying more than seven times the amount of ammonium nitrate involved in a Beirut blast which killed 218 people and injured a further 7,000.

Rupert Lowe, MP for Great Yarmouth, previously praised Peel Ports for "taking on this ambitious project" and allowing the MV Ruby to dock.

He said: "My office is in regular contact with the port and relevant authorities and we are closely monitoring the situation in case any action is required."