Preparations were being made late last night on the bid to rescue the Hoegh Osaka from being grounded in the Solent

Preparations were being made late into the night for what would have been one of the biggest and most expensive rescue operations ever seen in the Solent.

But after examining the vessell it was decided it had taken on too much water and that weather would not remain calm long enough to complete the operation.

A spokesman for the Maritime and Coastguard Agency said: "Following the completion of the salvors calculations this evening it has been decided that there will not be an attempt to refloat the Hoegh Osaka tomorrow.

"The salvors calculations revealed that more water has entered the vessel than previously thought. The preparation for the refloat will therefore take longer than the weather window will allow tomorrow.

"The alternative option of securing the Hoegh Osaka will be followed and preparations for the re-float will continue when the weather allows."

As reported by the Daily Echo, the 51,000 tonne car transporter was deliberately stranded on Bramble Bank after it began listing after leaving Southampton Docks.

The mammoth operation to refloat it - without causing an environmental catastrophe - is finely balanced on the whim of mother nature as gale force winds and heavy rain head towards the region.

The rescue operation is likely to cost £10m and could lead to the temporary closure of what is one of Europe's busiest shipping lanes.

It comes after dramatic developments yesterday when high tides at noon pushed the ship to become “lightly aground” on the sandbank.

Teams from global maritime experts Svitzer are spearheading the mission in partnership with the Maritime Coastguard Agency, diving teams and shipping experts from Southampton.

Last night Svitzer's top specialists were using computer models to make last minute calculations as a dress rehearsal when the plan is put into reality.

Crews have spent three days surveying the ship and repairing damage to the hold after one of the diggers it was carrying smashed into the side of the vessel puncturing a hole on the sixth deck.

The ship's cargo of 1400 cars and nearly 100 items of diggers and plant machinery and its 500 tonnes of fuel is secure.

When the plan can be carried out two tugs will begin towing the vessel to deeper water while it is still listing at 50 degrees.

There will be a 500m exclusion zone while the convoy crawls at a speed of around three knots to a temporary location so they can begin righting her without obstructing the shipping passage.

At last night's press conference at Southampton's Grand Harbour hotel Bram Sperling, salvage master for Svitzer, said their success rests on a delicate balance and added: “When we feel that it's doing what we expect we will try and get her to deeper water.”

He added: “We have taken out some of the water that was leaking into the vessel so it should reduce the draft.”

Once sheltered they will use a “complicated sequence” to pump ballast into the vessel so it can eventually become upright. The cargo will remain onboard throughout, along with the vessel's fuel.

The second option, if weather hampers the delicate operation, would involve anchoring the ship in place on the sandbank and waiting for conditions to improve in coming days or even weeks.

The ship may also have to be anchored halfway through being moved if conditions also changed, he said.

Hugh Shaw secretary of state for the Maritime Coastguard Agency thanked everyone involved for their “tremendous efforts” and added: “The main priority is the protection of the environment and re-floating the ship in a safe manner without damage to the environment.

Bram Sperling and Hugh Shaw

“We want to make sure this is a successful operation with the least disruption to the port but also the local population who use the port for recreational reasons.”

Salvage expert Captain John Noble said the job could be “extremely perilous” and added: “The key really is to get the ship upright so she can be floated away.

“Good luck to them, I hope it works, because if they do get the ship into a position where it could refloated then the cargo could be saved.

“If they get it done quickly then the cost of the operation could be down to £10m or less. It only becomes really expensive when it drags on.”

He said the salvage teams would “undoubtedly” look at the operation to rescue the MV Cougar Ace, a vehicle carrier which lost stability and ended up on its side at a similar angle to the Hoegh Osaka in 2006 and was towed by tugs from a location west of Alaska back to port, before being righted and eventually repaired.

A spokesman for ABP said: “Whatever happens disruption to the port of Southampton will be kept to a minimum.”