A container ship that has blocked the Suez Canal for nearly a week was partially refloated on Monday, raising hopes that traffic will soon resume on one of the world’s busiest shipping routes.

However, a Dutch salvage company that has been brought in to assist with the dislodging effort has cautioned that more work is needed before the mammoth vessel is totally free.

The Panama-flagged ship, Ever Given, was "successfully" unstuck after it responded to pulling, towing and digging efforts by salvage teams working around the clock, the head of the state Suez Canal Authority (SCA), Osama Rabae, said.

The high tide overnight accompanied by a full moon aided in the efforts to dislodge the ship at around 4:30 am (0230 GMT) on Monday, maritime service provider Inchcape Shipping said.

"The course of the vessel has been readjusted significantly by 80 per cent. The vessel’s stern has moved away from the canal bank by 102 metres," Rabae said in a statement.

While the ship's stern has been cleared from the side of the canal, "the bow is still completely stuck," Peter Berdowski, head of the Boskalis dredging and heavy lift company, told Dutch radio early Monday.

"Something is moving, that's the good news," he said, but it's too early to give the all-clear.

He described the bow as still "lying on the beach like a whale."

Salvage crews hope to free the ship completely with the help of another tugboat during the course of the day, Berdowski said.

If that does not succeed, containers might have to be unloaded after all, a process he described as being very time-consuming.

Towing operations were due to resume at noon local time, during the high tide when the water level swells to the maximum height of 2 metres, which should allow a complete change in the vessel’s course, according to Rabae.

TV images showed tug boats around the ship, which is loaded with around 180,000 containers, in the run-up to the new attempt.

The 400-metre-long-vessel is then due to sail to the Great Lakes area, a wider section of the canal, for technical inspection.

The tanker veered off its course on Tuesday when the crew lost visibility during a sandstorm, resulting in a huge traffic jam.

The blockage of the canal by the ship, which is almost as long as New York's Empire State Building, disrupted supply chains and sent ripples through global markets as it remained wedged across the waterway.

According to the canal authority, around 370 ships were waiting for passage on both sides of the canal, including 25 oil tankers. Financial news wire Bloomberg reported there could even be as many as 450 waiting ships.

The canal will work round the clock to clear a backlog of the vessels anchoring in the waterway’s waiting areas, Rabae said Monday.

He hoped that the noon towing operation will take a short time, estimating it at two hours.

"By [Monday] night, traffic, God willing, can resume if things go well," the official told Egyptian privately owned television Extra News.

Some shipping companies have already rerouted their vessels to avoid the canal. International shipping firm, Maersk Group, said it had redirected 15 vessels around Africa’s Cape of Good Hope.

Maersk Monday predicted that clearing the backlog of vessels could take at least six days for the “complete queue to pass, conditional to safety and other operational circumstances.”

The Suez Canal, which connects the Mediterranean to the Red Sea, provides the shortest shipping route between Asia and Europe.

The blockage was costing the canal operator 13 million to 14 million dollars in losses per day, according to SCA official.

At least 18,840 ships passed through the canal last year.

The Suez Canal provides one of Egypt's main sources of income, alongside tourism and remittances from expatriates.