The massive container ship blocking Egypt’s Suez Canal and causing havoc for international shipping has been “partially refloated”, according to a canal services firm.

The 400-metre Ever Given is still partly stuck in mud, but the development has raised hopes the busy waterway will soon be reopened for the huge backlog of ships that has built up over the last week. Work is now under way to move the cargo around inside in the hope its balance will shift.

The boat got jammed diagonally across a southern section of the canal in high winds on Tuesday, reportedly after being blown off course. In doing so, it halted traffic on the shortest shipping route between Europe and Asia.

After further dredging and excavation over the weekend, rescue workers from the SCA and a team from Dutch firm Smit Salvage worked to free the ship using tug boats in the early hours of Monday, two marine and shipping sources told Reuters.

Video posted on social media appeared to show the ship had swung around, opening space in the canal. Other footage included cheering and ships’ horns sounding in celebration.

At least 369 vessels were waiting to get past, including dozens of container ships, bulk carriers, oil tankers and liquefied natural gas (LNG) or liquefied petroleum gas (LPG) vessels, SCA chair Osama Rabie said.

“It is very possible that by today noon shipping activity would resume, god willing,” Rabie told Egyptian state television on Monday.

“We will not waste one second.”

The SCA has said it can accelerate convoys through the canal once the Ever Given is freed.

“We have movement, which is good news. But I wouldn’t say it’s a piece of cake now,” Peter Berdowski, the CEO of Smit Salvage’s parent company Boskalis, told Dutch public radio.

High pressure water would be injected under the bow of the ship to remove sand and clay but if that was unsuccessful, containers might have to be removed from the ship, which would cause a considerable delay, he said.

A source involved in the salvage operation said they were re-ballasting the ship and expected that with a favourable tide, cargo would not need to be removed.

“The good news is she’s moved. But she is still stuck in the mud. A second large anchor-handling tug will arrive this morning. Hopefully they will be able to pull her free.”

The ship’s technical manager Bernhard Schulte Shipmanagement (BSM) said operations to ensure the vessel is completely refloated were still going on.

About 15% of world shipping traffic transits the Suez Canal, which is a key source of foreign currency revenue for Egypt. The current stoppage is costing the canal $14m to $15m (£10.2m to £10.9m) a day.

Shipping rates for oil product tankers nearly doubled after the ship became stranded, and the blockage has disrupted global supply chains, threatening costly delays for companies already dealing with Covid-19 restrictions.

Some ships were rerouted around the Cape of Good Hope, adding about two weeks to journeys and extra fuel costs.

A note from AP Moeller Maersk seen by Reuters said it had so far redirected 15 vessels around the Cape after calculating that the journey would be equal to the current delay of sailing to Suez and queuing.