About 100 tonnes of cargo were being removed each day

The weather stopped the salvage operation on Wednesday, and the Maritime and Coastguard Agency (MCA) says sea conditions are getting worse.

It is feared the rig could also end up on rocks unless it is moved because it has been listing.

There are also concerns about the safety of sightseers, as hundreds of people have been coming up to the cliffs every day to see the vessel.

Sea swell

Salvors will return to a conveyor belt method to remove the shredded plastic, but that will not be as fast.

But rough seas have continually hampered efforts to clear cargo.

A two-tonne grab claw on the rig and other equipment have already been washed into the sea.

An MCA spokeswoman said: "The operation with the rig was always a risky one relying on a window of good weather."

One fear is that people are going to fall off the cliff Steve Winston, Emergency Planning Officer

"Unpredicted levels of sea swell have put a stop to that."

There is also concern that onlookers might put themselves and nesting birds at risk.

Although the salvage area has been roped off, some people are still taking risks.

Emergency Planning Officer Steve Winston said: "One of our main fears is that people are going to fall off the cliff.

"Police will visit the site this weekend and over Easter weekend just to enforce the message."

The Mulheim was carrying 2,200 tonnes of cargo when she ran aground between Sennen and Land's End on 22 March.

The removal equipment is to be inspected for damage and the vessel's remaining cargo is to be cleared via a mechanised conveyor system when weather permits.

Daily inspections

Up to half the Mulheim's cargo has already fallen into the sea.

Local authorities are carrying out daily inspections of nearby beaches for washed up plastic. So far only a small amount has been recovered.

Although the plastic is not coming up on the beaches, fishermen have reported picking it up in nets and fear it could be affecting catches of spider crabs.

However, boat insurers have said any reasonable claim for loss of earnings will be considered.

The vessel's fate will be decided after her cargo has been cleared.