General Osama Rabie, Chairman of the Suez Canal Authority, says water has started running underneath the vessel.
He added: “We expect that at any time the ship could slide and move from the spot it is in.”
If the tugboat efforts fail to move the ship any further however, crews may have to start the process of removing some of the 18,000 containers on board in order to lighten the load – something Mr Rabie said he was reluctant to do.
The blockage is costing Egypt up to $14 million in revenue each day the canal is closed and is holding up $9.6 billion worth of goods.
But John Denholm, president of the UK Chamber of Shipping, says transferring the containers to another vessel or the canal bank would involve bringing in specialist equipment, including a 60m crane, warning: “If we go through the lightering process, I suspect we’re talking weeks.”